I have signed up to a Flickr Pro account for several reasons :
- To have a external backup of our photos
- To let me use Flickr as a proxy for serving images for the blog(s)
Normally all photos go into iPhoto - so this seems to be one of the sensible "hubs" for exporting to FLickr from, but the only direct plugin I could find was a "pay for" piece of software - until I thought of PixelPipe, which has a client for the iPhone, and a plugin for iPhoto.