One of the many things that I missed when I moved from Windows to Mac was the Flickr Uploadr for Windows. I did bought FlickrExport, an iPhoto plugin that makes it easy to upload photos to Flickr. That’s an awesome software and worth every penny.
However, Flickr released the official Flickr Uploadr for Mac OS X recently and this should be one good software to have if you use Flickr.
But after using FlickrExport, it will be difficult to move away from such an awesome software. Currently, Flickr Uploadr have no option to set Sets or Send to Groups and it do not show your tags.