Perhaps one of the most anticipated fighting games in 2011. I am having fun playing this game, but some flaws generally holding this game back from becoming a masterpiece.
Storyline
Source: http://en.wikipedia.org/wiki/Marvel_vs._Capcom_3:_Fate_of_Two_Worlds#Plot
There, that's the whole story of the game. Besides that, after beating the final boss with a specific character, you will get to view his/her/it's ending. Some are good, some are not. The ending only explained using texts and comic illustrations without any voiceover, which dampens the ending's impact to players. Some endings have cameos of unplayable characters, like Ghost Rider in Dante's ending.
I have very mixed opinion with the storyline, as it is not well explained in the game, and most of the endings for each characters in the game are quite disappointing to me. Only some are good, like Dante's ending and Deadpool's ending.
Gameplay
The game plays like previous MVC games, except with more simplified controls. There are 4 main attacking buttons. Light attack, medium attack, hard attack, and launcher attack. In this game, it is much easier pulling off Aerial Combos that can devastate your opponents.
As in many fighting games, the objective to win a match is to defeat all characters of your opponent.
You can play with three characters in your team, and you can choose either Marvel side, Capcom side, or both together. There is a lot of characters to be used in this game, as there are more than 30 characters to be used in the game, with some unlockable characters as well as two DLC characters currently.
Each characters have their own pros and cons, depending on player's point of views. Dante has a large arsenal of techniques to fight various types of opponents, but he has lower attack power. Chun-Li has great speed in movement and attacking, but most of her attacks are close ranged. The main idea to make a solid team in the game is to get characters that can offsets' another's weaknesses, like teaming up Iron Man with Chun-Li to offset her lack of ranged attacks, or Hulk with Phoenix to offset her very low HP.
Gamers have each of their own fighting styles to fight another gamer. Some might use a team of Iron Man, Akuma, and Ryu to dominate his opponents in pure Hyper Combo moves as well as projective attacks, while some uses a team of Dante, X-23, and Wolverine to attack his opponents up and close to prevent them from counterattacking. It all depends on you.
Each characters have their own special moves, like Ryu has Hadouken and Shoryuken as his special moves. Some of their special moves have advanced forms called Hyper Combos.
The gameplay is awesome, except several flaws. Some characters are unbalanced, lack of fighting modes, etc. However, this does not dampen the game's amazing gameplay system as well as addicting.
Storyline

Play as Capcom or Marvel characters, and defeat Galactus to save the world. Simple as that. But not all characters have good intentions after defeating Galactus, like Wesker.
I don't know if the game has a story, but apparently, there is one:
Doctor Doom has assembled the greatest villains of the Marvel Universe and has joined forces with Albert Wesker in order to unite their respective universes in an effort to conquer both. However, this course of action awakens a great and powerful threat that could potentially destroy both worlds. It is up to the heroes of the Marvel and Capcom universes to put a stop to this evil before it is too late
Source: http://en.wikipedia.org/wiki/Marvel_vs._Capcom_3:_Fate_of_Two_Worlds#Plot
There, that's the whole story of the game. Besides that, after beating the final boss with a specific character, you will get to view his/her/it's ending. Some are good, some are not. The ending only explained using texts and comic illustrations without any voiceover, which dampens the ending's impact to players. Some endings have cameos of unplayable characters, like Ghost Rider in Dante's ending.
I have very mixed opinion with the storyline, as it is not well explained in the game, and most of the endings for each characters in the game are quite disappointing to me. Only some are good, like Dante's ending and Deadpool's ending.
Gameplay

Plays like previous Marvel vs. Capcom games, but with better controls.
The game plays like previous MVC games, except with more simplified controls. There are 4 main attacking buttons. Light attack, medium attack, hard attack, and launcher attack. In this game, it is much easier pulling off Aerial Combos that can devastate your opponents.
As in many fighting games, the objective to win a match is to defeat all characters of your opponent.

Every characters have their own strengths and weaknesses, but some characters are plain cheating.
You can play with three characters in your team, and you can choose either Marvel side, Capcom side, or both together. There is a lot of characters to be used in this game, as there are more than 30 characters to be used in the game, with some unlockable characters as well as two DLC characters currently.
Each characters have their own pros and cons, depending on player's point of views. Dante has a large arsenal of techniques to fight various types of opponents, but he has lower attack power. Chun-Li has great speed in movement and attacking, but most of her attacks are close ranged. The main idea to make a solid team in the game is to get characters that can offsets' another's weaknesses, like teaming up Iron Man with Chun-Li to offset her lack of ranged attacks, or Hulk with Phoenix to offset her very low HP.

Morrigan is not only hot in the game, but she's a good fighter.
Gamers have each of their own fighting styles to fight another gamer. Some might use a team of Iron Man, Akuma, and Ryu to dominate his opponents in pure Hyper Combo moves as well as projective attacks, while some uses a team of Dante, X-23, and Wolverine to attack his opponents up and close to prevent them from counterattacking. It all depends on you.
Each characters have their own special moves, like Ryu has Hadouken and Shoryuken as his special moves. Some of their special moves have advanced forms called Hyper Combos.

Hyper Combos are not only flashy, but are very devastating.
Each characters have their own Hyper Combo moves. Hyper Combo moves are advanced techniques that can damage your opponent's character a lot. Most characters have 3 Hyper Combo moves, like Dante has Hyper Combos of Million Dollars, Devil Trigger, and Devil Must Die. In order to do a Hyper Combo, you need to deplete your Hyper Gauge, which is filled by attacking your enemies, or getting hit by your enemies. All characters Hyper Combos that requires only 1 bar of Hyper Gauge, but some require more than 2.
Crossover Combination are a combination of three Hyper Combos to defeat your enemies. If one of your characters are KO'ed, only 2 characters will carry out Crossover Combination. Although it is a good move that can depletes your opponent's characters health fast, it is not advisable to use it often as it depletes a lot of your Hyper Gauge.

Deadpool is the most craziest fourth wall breaker in video games that I have ever played.
When you see your character has low health, you can switch out immediately with another character to prevent him/her from being KO'ed. This is vital as having KO'ed members in your team can put you in a disadvantage against others. Also, you can use Assists to help your character in assaulting your opponents. You can set up a different Assist move for each character, like Jam Session for Dante, Uni Beam for Iron Man, and Hadouken for Ryu. Setting up proper Assist moves for each characters will help out a lot in playing this game.
Blocking enemy's attacks are important to preserve your health. Blocking is essential when your opponent uses a Hyper Combo or Crossover Combination, as both can deal huge damage, especially the latter.
There are few game modes in this game, like Arcade mode, Mission mode, and Training mode. Arcade mode requires you to fight several rounds to view an ending, Mission mode requires you to perform moves to proceed, and Training mode allows you to hone your gaming skills. However, the main draw in this game is the online matches.
The gameplay is awesome, except several flaws. Some characters are unbalanced, lack of fighting modes, etc. However, this does not dampen the game's amazing gameplay system as well as addicting.