/me looks around and says “Snapzilla“?
Flickr? The free offering is fine if you're not wanting to store many, and you can easily share them here. Of course I'm one of those cray-cray SL fashionistas who have a Flickr Pro account. Seriously I find it hard to recommend Flickr Pro unless you take lots of rl pics with a “real“ camera, or do a lot of virtual photography in either SL or Games.
I use gyazo for quick sharing of things I see or wear that I don't feel the need to do a full-on Ctrl+~ screenshot uploaded to Flickr for.
Imgur I've not used, but if I was a serious memester I'd probably be using it for my "Me me's“