The only RPG setting I'm TRULY HONESTLY bored with is "Generic Idealised Medieval" Fantasy like you see in Oblivion, Two Worlds and tons of other games (I'm looking at you DnD Titles!). IF you MUST make a Medieval game, give me real, gritty, gross, paranoid, oppressive, fanatically religious, SCARY medievalism... basically a Game of Thrones or Warhammer Fantasy RPG...
However what I would like to see more?
An RPG based around Non-Kung-Fu Movie Mythical China (Yes, contrary to popular belief there IS more to an asian setting than martial arts).
A Clock Punk RPG set in the Renaissance
A full blown Space Opera RPG, complete with playable Starship Battles and an Epic Galaxy Crossing Story.
A Steampunk Western RPG, no not developed in the west, I mean a legit WESTERN RPG... Wild Arms is too much Fantasy not enough Western! I want MORE I say!
And what you would do with a World War RPG intrigues me... so I would LOVE to see one made.