You lose any presets you have stored in Audition's memory, too. However, there's a file that has all this information, and if you copy it before you uninstall, you can load that info back into the reinstalled version, and you have all your presets again. Somebody help me with this. What's that file called? It's an .ini file I think, right?
Back up is really essential thing when you want to go for re-installation... Never ever forget to do that...I once did the reinstall and as a result I got everything lost I should have done a backup copy before.