I too am having issues with the tooltips and Desktop Manager, though if I had to be honest I'd say in general the tooltip over the contact list is the most annoying part of the UI.
Is there an option to just disable it? I'd really like that a lot, just get rid of it totally
If you're adventurous you can try the beta yourself; get it from beta.adiumx.com. But be sure to follow the recommendations and back up your prefs first. 0.8 beta does reset a lot of your 0.7 settings, so be prepared to take some time to reconfigure.