There are many sites that are popping up around the web that deal with photography and blogging, i am not going to list them all, and i don't think one is better then the other, they are all different.
What i do want to talk about is how you use the those sites or multiple sites sometimes. Some sites like 500px have a dislike button i really am not sure why there is a need for it, if you don't like someone's picture just move on, do not comment on it, there are tons of other pictures, but it is what it is, i am sure there is a meaning for it.
With that said when you browsing photo's or blogs and you come across something you like leave that person a comment no matter which site it is on. Also just because some famous photographer is using a specific site does not mean you should jump into it as well, evaluate your options, just like photography itself there are many styles of it(landscape, city, street, nature), depending on your style some site are better then others.
I just watched this interview with Trey Ratcliff and i advise everyone to watch it or just listen to it as it speaks about being open, being yourself and not worrying about so much if people like or dislike your photos: http://youtu.be/Us9S8gVFzmo