Just a hunch that for Best Actor it's going to be Peter O'Toole for the movie that nobody's seen ("Venus") vs Forrest Whittaker ("Last King of Scotland") or Leo (for whichever pic he's nominated for--probably " Departed").
For Best Actress, Helen Mirren vs Penelope Cruz. A nominated bridesmaid again: Meryl Streep (will she ever get that 3rd Oscar?) Darkhorse: Annette Bening.
I agree with you about the Best Actor race. It's a three-man show right now between O'Toole, Whittaker and DiCaprio. There is buzz on a few sites and Peter Travers of Rolling Stone is pushing Jack Nicholson into the lead actor category for his role in The Departed. If AMPAS puts him there, that could throw the entire category out of whack and could shut DiCaprio out. I think O'Toole and Whittaker are in.
I disagree with you a bit about the Best Actress race. The buzz for Kate Winslet's performance in Little Children is outstanding. I think you have to consider her. I agree that Helen Mirren is a lock for a nom and probably the frontrunner, particularly now that the film is getting such good buzz. That said, Imelda Staunton was in the same place for Vera Drake. We'll see. I say it's a three-woman race with Judi Dench (Notes on a Scandal), Meryl Streep (The Devil Wears Prada) and Annette Bening (Running with Scissors) right behind. If they market Bening (or Streep) for Best Supporting, that could make a difference as well.
Thanks to Girl Arkansas for posting a link to the trailer for The Departed, which opens this weekend.