The plot can be confusing if you don't get enough dossier info to really uncover people's motives and the web of character relations. However, after a few playthroughs most of the initially apparent holes will be plugged and it'll make sense.
Though the plot might have taken a bit of a backseat, the writing is fantastic (it's Chris Avellone, after all), as is the cinematic direction. The choice and consequence is unrivaled by any other recent RPG - I've played through the game three times now, with each time having notably different things happening throughout the game, in response to my actions (not only the blatant ones, but things like shooting innocent guards instead of knocking them out in the course of a mission). I'm sure I haven't uncovered all of the possible branches yet, either.
The gameplay isn't spectacular, but I don't get why all the reviewers ripped on it. It's certainly as good, if not better, than Mass Effect 1. The graphics, as well, are better than those of Dragon Age, yet Dragon Age didn't get panned for outdated visuals. The AI is goofy, but it's not gamebreaking.
As for bugs, I've seen maybe five or six bugs, total. Most of them are graphical and fairly minor.