If any of you haven't seen any of Eddie Murphy's two standup videos (Delirious and Raw), you really should. They are incredibly funny and still very current considering they are getting on 30 years old. Richard Pryor's old routines are also very, very good as are Chris Rock's.
Of the current crop, I must admit I love Frankie Boyle. Whilst I can see why he generates angst from the wider public with his contentious material; isn't that what comedy is about? Nothing should be taboo in standup and I simply do not get why people moan about him or his content. You know what's coming so if you don't like it, don't watch it - it really is that simple
Dara O'Briain is another firm favourite. Went to see his show about 12 months back or so and it was superb. Incredibly intelligent guy and extremely witty.
Also like Rhod Gilbert, Jimmy Carr, Kevin Bridges and a few of the other usual suspects mentioned in this thread.
I'm also another who has never liked Bill Hicks or George Carlin for that matter. That said, there are very few US comedians I do like as I find their humour (in general) very different to ours.