For those of you using 6.5.x, I came across a program the other day called Ameba that allows you to change the behavior of the X and start menu buttons. You can set it so a short/long press of the X actually closes a program as opposed to just throwing it in the background. There are other settings as well. I did see it mentioned a long while ago in Calkulin's thread(I wish it wasn't locked) but figured I throw it out here again, as it seems to be working extremly well.
Here's the thread at XDA(I'd attach the program but I can't upload from work)...
http://forum.xda-developers.com/showthread.php?t=583002
The only thing I had to do was to throw Arkswitch into the exceptions list so it wouldn't close that program on pressing the X.