@Gary86,
Someone above did reinstall iLife but did so because for an unrelated larger issue that necessitated a complete reinstall of OSX. At that point, they just didn't update iPhoto beyond what was on their original install disks. This method is, obviously, extreme and I don't think the person would have done it just to fix the duplicate Event issue; I know I wouldn't especially since Apple is supposed to be working on a fix.
That said, an easier solution was proposed by someone else by using Time Machine to revert to the 9.2.0 version of iPhoto. Personally, I don't recommend that either because it might mess with future software updates since if you grab the iPhoto.app package from finder using Time Machine you will still have "Receipt.pkg" files in your Macintosh HD/ folders from subsequent iPhoto versions. Software Update might be smart enough to disregard this, but who the heck knows?
For the time being...continuing to add to this thread may be our best option.
1) It keeps Apple abreast of how broad the issue is, especially as new "sufferers" add their experience.
2) Someone may identify a magical workaround...here's hoping
3) Public service to those who haven't yet updated to iPhoto 9.2.1, aka folks smarter/more wary than us 🙂
Anyway...my continued 2 cents...