Corey, after installing successfully TD3 I was afraid to remove TD2 fearing that it may remove elements of TD3 necessary for operation. I had nothing to lose (everything is backed-up properly) however I was nervous. After removing TD2 it was obvious that nothing from TD3 had been touched.
Could you make a note on the download page (or somewhere in the main site) that removal of TD2 will not affect in any way any files used by TD3 (including activation, data stores etc.)?