Pitchers can go through massive hot and cold streaks throughout the entire season. It's only week 2. There are 162 games. Don't think of dropping a SP unless somebody better happens to be around.
Lilly*-- ehhh, I'm worried his best years are behind him. See what he does over the next few starts, but don't necessarily play him until he performs.
Dempster** -- See above, Lilly
Bucholtz*-- He'll be fine, although not quite as good as last season
Beckett*--- He's no longer an ace, and perhaps not even a number 2...but he'll be serviceable and provide k's. It's also likely he'll be hot and cold to extreme degrees, to be careful when to start and when to bench.
Shields-- He's become a little underrated. Nothing great, but nothing special.
Drabek--- As the other poster remarked, a wonderful young prospect. But if he fails miserably over the next few weeks, he'll be sent down anyway.
Which SP are on your waiver wire?