@Riot: What's the liklihood of a vision based support champion?
There are a lot of supports that have vision granting abilities, such as Thresh's Lantern, Gragas's Barrel Roll, Leona's ulti, etc, but will there ever be a support that is all about granting and denying vision?
While there are more than a few champions that have the ability to hide themselves, only two have abilities that actually deny vision, those being Graves and Nocturne. As well, very few have the ability to safeguard themselves with vision granting traps, those being Teemo, Nidalee and Caitlyn. There are only three champions which utilize long range champion specific vision, those being Warwick (situational though), Twisted Fate and Rengar.
Supports are meant to be utility champions, and what greater utility is there than vision? Thresh can peel and Sona can heal, but in the end, preventing a fight from ever happening is even more powerful.
Vision control is immensely powerful and sparingly sprinkled over a small cast of characters. Will there ever be a support with such an interesting gimmick as granting and denying vision?