I liked The Departed very much. I'm still kind of stunned by the scene of Matt Damon and Leonardo DiCaprio on the phone with one another but not saying anything -- it was easily the most suspenseful part of the movie, even though there was quite literally nothing at all happening on screen. Good stuff. I was impressed by both Matt Damon and Leonardo DiCaprio, but less so by the supporting actors. Nicholson was Nicholson; he's fine in his role, but I think he's is always a lot better when he tones down the outrageous persona he's developed over the years (like in About Schmidt, or Reds). And I'm not sure I fully understand what the Academy voters saw in Mark Wahlberg's performance. Again, it wasn't a bad performance, but I thought Alec Baldwin's was better.
So, having now seen all five Best Picture nominees, what's my verdict? Well, here it is: I dunno. Scorsese is a mortal lock for Best Director, and in hindsight it's a good thing that he didn't win for Gangs of New York or The Aviator, because The Departed is a far better film than either one, so no one will be able to say that his win this year was a consolation prize for not having won before. So does that mean The Departed will win Best Picture? Hard to say. Back in the day, I would have said yes, but in recent years the trend seems to be toward giving Best Picture and Best Director to different films. The Departed is awfully violent, and I can see that turning off some older Academy voters. On the other hand, I would have said the same about The Silence of the Lambs, so it doesn't require a stretch of the imagination to see The Departed winning Best Picture. That said, my gut says Babel will win Best Picture.
