I found the photo portfolio site 500px.com a while ago but did not pay much attention to it. Until a couple of days ago when the site was brought to my attention again.
I’m using Flickr for some time now and that works fine. I store ALL of my photos on Flickr and even photos from my family that I received. In that case, it is not always necessary to be to hard on the quality of the photos. I also store the not so good ones, as a backup in case something happens with my regular backup.
Therefore I decided to use 500px.com for only my best photos together with my regular portofolio site http://www.vdsar-photo.com/. 500px.com offers some features like a blog and wall that Flickr does not offer. I have not found groups on 500px yet ;-(.