The_Scrivener said:
Simply put, this is a genuine case of a "love it or hate it" game... The story is very weak boiling down to "there's an evil mega-corporation, you are a mercenary who got cheated, go get them boy", the gems being that the mercenaries from the first game are NPCs of importance now.
I mostly play it single player, and I've played it multiplayer, difficulty-wise it's the same thing, since the enemies get stronger the more players join you, on the other hand so do the spoils of war get better.
In the end: give it some time, get past the first few missions, if the crude humor didn't catch you, if the design isn't your thing, if the witty cartoonish characters don't please you... Then let it go, for me, those are the elements that keep me coming back to Borderlands 2.
If I may suggest: in case you're looking for a more serious tone of post-apocalyptic scenario, a much better story (though still mediocre...), and some jaw-dropping graphics, go for Rage. It's from the guys who made Doom and Quake, and it's basically all the hatred of those games with a post-apocalyptic setting, it's an old-school shooter with a few twists to it (like car races, Mad Max style). Also, keep an eye out for both Fallout 3 and Fallout: New Vegas, they are RPG's with a somber tone and some acid humor, the story though is pretty weak (more so in Fallout 3), but it's one of those games where the most fun is being "part of that universe", like most RPGs are (or were should be).