I think you'll be able to get a real good deal on a 2001. Especially if all of the changes to the IS for 2002 are true, then most dealers will be trying hard to get rid of old stock to make room for the manuals and upgraded auto models.
If you do decide to go with a good deal on the 2001 make sure you lease it instead of buying. Then you'll come out on top all the way around. You'll get a great car and its value will be guaranteed at the end of your term.