First difference it has a viewer built-in where you can preview your video downloads (haven’t tried any videos other than .mov files).
The second difference is that in the menu bar at the top of the screen it tells you the current upload and download speed of the application which comes in handy if the app is in the background or minimized in the dock.
The third difference is it has a built in portal to it’s online forum which is nice. Since it is still a relatively new application the forums are too big but there seems to be a fair amount of people (over 600 registerd users i’m member # 666) in the forums who could help you if you had problems with the app.
I still like poisoned but I will give XFactor a chance. If by chance you are one of the people out there who doesn’t like any of the current p2p choices on the Mac give XFactor a try.
8 out of 10 for a very solid beta release.