Pro Conflicts -- Early reports indicate that some software compatible with System 7.1 may not work properly with System 7 Pro (see article below), and that some older software may need to be upgraded to the current version. Before leaping into System 7 Pro, which isn't exactly critical, make sure you're not running anything that will cause conflicts.
Pythaeus tells us that you'll need to use Gatekeeper 1.2.8, released earlier this year; Now Toolbox 4.0.1p; Silverlining 5.28; AutoDoubler 2.0.2 (to be safest, turn off the DD icon brand); and After Dark 2.0x, though some modules, including Rain and Boris, might not work. The various publishers of these utilities should be contacted for information. (Gatekeeper is freely available on a variety of FTP archives such as <sumex-aim.stanford.edu> and other online services, and there's a free After Dark Updater utility floating around.)
Also, current versions of BeHierarchic, Super Boomerang, More Disk Space, HAM, and Double Trouble are reportedly incompatible with System 7 Pro, and need to be updated by their publishers, whom you should contact for the latest information.