I just discovered 500px.com. In fact, an hour after hearing an interview with one of the founders, I had a site up and 50+ pictures uploaded. I always thought Flickr was too ugly and filled with too much thoughtless card dumps from family parties and just couldn't get into it. 500px.com is for photographers--really beautiful interface and design, as easy as it can get to navigate, upload and share. Anyone else try it out yet? I think they are adding 1000+ photographers a day!