WordPressExport
WordPressExport is an iPhoto plugin which allows you to export images to your WordPress powered blog. This plugin is useful for anyone who use WordPress as a photo gallery software. You can easily upload photos by selecting photos from within iPhoto.
WordPressExport costs £5/€8 . Only 4 images may be uploaded per post in the unregistered version.
For those with a Movable Type Blog, you can use Photon to export photos to your MT powered blog.