OMG! This site was SO much fun! Flickr is incredibly user friendly. I posted some pictures on the site just to see how things would show. Take a look! It was easy to add tags and organize my photos.
The site has a lot to offer...I really enjoyed surfing through the different groups...I even joined one. I love pictures of Houston's skyline, so I joined a group that specializes in posting pictures strictly of our gorgeous skyline (I don't think that we get our props for our downtown area). Here's one of my favorite pictures that I found there.
Also...from what I can tell, libraries are using Flickr for all kinds of things...several of the groups I found are using the site to chronicle the libraries in their area...I thought that was neat.