Quote from DavieshI would back up your AddOns folder (as you should always do when moving to a different updater), but beyond that the Curse client seems to be working well.
Agreed, it's been working fine for me since Monday when I moved over. The first few times it ran it kept asking me which version of some duplicate names I wanted, but it's stopped doing that. I plunked it directly down on top of ~100 addons, btw, with no significant problems. My only wish-list items at the moment are a "recent actions" frame so I can tell which mod just borked my UI, and a menu item to step back to previous versions, because people keep pushing dry-coded and broken addons to curse.