Great list of tips and features for Flickr's new iOS application. Iparticularlylike number 3:
3. Apply a single filter to multiple photos at once. Did you fall in love with a particular filter? We’ve made it easy for you to apply it to multiple photos at once. You simply select the photos from your camera roll that you’d like to edit then go to the filter screen and tap and hold the filter that you want for your photos. And just like that, all of your photos are Panda-ized.
I also didn't realize that you could manage your Flickr Groups from within this application as well. This is a very feature-rich application.