Would it kill them to document this kind of feature?!
Sharing via the Shared Folder -- Another major annoyance with versions of iPhoto prior to iPhoto '09 was that you couldn't just put your iPhoto Library in the /Users/Shared folder to share it among multiple accounts on the same Mac, since iPhoto always set the permissions on thumbnails to the account that imported the photos, preventing other accounts from editing those photos and having the edits reflected in the thumbnails.Hell's bells, this is huge for us. This means that I now have to think about either buying iLife '09 or buying a bloody new machine and getting it for free.
That limitation has now been fixed in iPhoto '09, so you can share an iPhoto library merely by moving it to /Users/Shared and then double-clicking it to open in iPhoto from each account. You may be prompted to repair permissions on the first access - click the Repair button to do that. Note that this also works for storing an iPhoto library on an external hard disk that's shared among users or on a network volume for access across a fast network.
Only one person may access a shared iPhoto library at a time...
The only things they could fix that would be comparable would be if they came up with a viable approach to managing video fragments in iPhoto or if Apple were to trigger the end of time by supporting iPhoto Library import/merging. (Yes, I know about IPLM, I've been a customer for about four years.)
Does Apple not want to sell anything?!
The only reason I can think of for this being undocumented is that there's a catch somewhere -- something that doesn't work quite right. I'll add a comment to that effect to the Tidbits article.