Today is apparently iPhoto export plugin day as in addition to the Facebook iPhoto plugin and updated FlickrExport plugin mentioned earlier, John Gruber at Daring Fireball brings our attention to ScriptExport from Nathaniel Gray. ScriptExport "allows you to 'export' your iPhoto pictures and movies by processing them with shell script." A script can can be done either at the start of the export, on a per item basis, or at the end of the process. He has some example scripts in the documentation. This is probably only for the command line ninjas among us (i.e. not me), but it looks like it could be very useful if you're the type that would rather type mkdir than hit Cmd + Shift + N.
ScriptExport is a free download.
[Via Daring Fireball]