It's not that it sucks, per se, it's just....easier. Online has been improved greatly and Epic have patched a lot of the early glitch issues so that the meatflag on one of the modes no longer stays fifteen feet in the air taking pot shots at everyone else. But if you're expecting something challenging like Raam at the end of Gears 1 then you'll be sorely disappointed - there are no really hard characters to fight, and coming from someone like me who couldn't shoot an elephant in a cardboard box this is saying something.
The ending might be a little deflating as well - again, Raam provided a great deal of "hell, that was tough but I did it". This time around you'll probably be a bit "lol, wut?". Still, they went with a slightly different angle this time with a different, more emotional storyline...I'd still highly recommend it to anyone, just don't be thinking it'll be a tougher upgrade to Gears 1.