VERY IMPORTANT! (well, quite anyway)
From the 10th November 2008, USA residents will no longer be able to open accounts at any online casino that uses Microgaming software. This is a huge proportion of the casinos represented on this and many other websites. However, any Americans who have opened an account on or prior to the 9th November 2008 (Sunday) will be OK to continue playing.
See this list of USA casinos for up-to-date information on a State By State basis.