In case you haven't noticed, command-tab now cycles between the current application and the last activated application. This is how the feature behaved in OS 9, and it was much missed in previous OS X releases (wherein it cycled through all open applications in the order in which they were opened).
Note that if you keep your dock hidden, you can actually hit and release command-tab fast enough that the dock barely becomes visible at all during the switch.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20020824215756748