Flickr4Twitter is the easiest way to upload your photos to Flickr and post them to Twitter. Flickr4Twitter was designed to let you upload your photos from Tweetie 2 to Flickr, but you can also post through the web with Flickr4Twitter.com.
Flickr4Twitter provides the following features:
* Returns a Flickr short URL http://flic.kr
* Autotags with “iPhone” and “flickr4twitter”
* Converts any hashtags in your tweet into Flickr photo tags
* Updates your Flickr photo description to the tweet you posted with URL for your tweet