Via Geektryant.com:

Thanks to EW, we have three official images from Star Wars: The Force Awakens showing off Supreme Leader Snoke and Maz. The magazine also conducted an interview with Andy Serkis in which he discussed his character.

He explained that when he did the motion-capture work for the character he didn’t exactly know what the character would look like.

“When we first started working on it, he had some rough notions of how Snoke was gonna look, but it really hadn’t been fully-formed and it almost came out of discussion and performance.”
EW went on to point out that there is a lot of speculation that Snoke might end up being Darth Plagueis, who was mentioned in the prequel films, but Serkis confirms that he…

“turns out to be… just Snoke.”
Serkis says that he was aware of the events in the previous films and says that his character is a new addition to the saga. Serkis goes on to explain his character:

“Supreme Leader Snoke is quite an enigmatic character, and strangely vulnerable at the same time as being quite powerful. Obviously he has a huge agenda. He has suffered a lot of damage. As I said, there is a strange vulnerability to him, which belies his true agenda, I suppose.”
More will be revealed regarding this character as the story arc for the new trilogy continues to play out. I’m very curious to know Snoke’s story. I’m sure whatever it is, it will surprise us all, unless the information leaks out early!