Apparently, the new patch has been having some problems under Windows Vista. Based on the description of the symptoms, I imagine this would be the same for other patches, so many of you may know this fix already. But then, some of you may have just upgraded to Vista. Anyway, here's the problem: the patch downloads OK, but the patcher fails to run correctly. According to Growl at Gitr's blog, this is because of permissions; the "normal" user on Vista doesn't have admin permissions, and therefore can't do things like run patchers.
Fortunately, Growl has an easy solution. Just right-click the WoW icon and select "Run as administrator" (as depicted); log in and WoW will spawn the patch download, which will inherit its administrator privileges and, in turn, spin off the patcher, also running with admin privileges. Safety is good, Microsoft, but Vista might be a little too safe for its own good. Couldn't we at least have an alert asking us if we wanted to authorize the patcher?