I've been using BetterTouchTool for a while now (for Magic Mouse, now on an MBP), however, I just tried Jitouch on my MBP, testing it out for about 2 hours. I find many of its gestures very hard to pull off, even after adjusting finger placement in settings. Many of the gestures not only do not register much of the time, but are not at all ergonomic, forcing you to bend your wrist and contort your fingers to attempt to execute the actions, unlike with OSX and BTT's gestures.
Jitouch has the much superior site and program UI though. BTT has a slightly confusing UI, and messy site layout--you need to poke around to find videos/instructions for some of the less intuitive gestures. But the developer has a great blog/Twitter, keeping us abreast of all happenings. And the program is frequently updated. And free.
For me, BTT is the easy winner. Much more powerful, customizable, and feature-rich. There are features that are indispensable, like windows snapping that's actually better than Windows 7's version. And most of the gestures do not force your hand into unnatural positions. It seems to have a few more bugs of recent, but the developer's already said he'll be addressing some of them when he's less busy with his thesis.
Jitouch is still a great program, but it's just that with BTT around, I haven't come across anything else that can even compete with it yet.
So now I'll delete Jitouch. Looks like I just right-click it in System Preferences to remove. Then delete it's plist in Home>Library>Preferences. Anywhere else I should look for lingering files? (That plist file is all I find when I do a search of "jitouch.")