The reason I wrote USR is because I found myself wanting to write ALL the RPGs, and releasing an 'engine', as it were, to the internet masses would help me see what's good and bad about the system before dedicating myself to a game. Having a rules-lite core for whatever game I want to write gives flexibility while cutting down much of the time it would take coming up with a new set of rules for every game.
I currently have 3 games in the pipeline that will run on USR's fuel: Derring-Do!, DemonLord and Dwellers (I seem to have a thing for Ds). I want to see at least one of those come to fruition this year - at the moment I've done most work on Derring-Do!, a pulp hero game set in modern times but in a weird 1940s city. DemonLord will be released not as a full rulebook, but as a series of gamebooks which add rules as they go. As for Dwellers, a time-travelling game, I have the concept and story written out as well as a list of specialisms, but that's pretty much it.
But what's in store for USR beyond these games, assuming that they will all come to pass?
Well, I would want to support the current USR line, releasing supplements and adventures (GM and solo). Beyond that, I'd love to write a fantasy/sci-fi game, where alien technology has become available in a fantasy realm, so you have dwarf-piloted warp freighters and exciting swashbuckling action all in one setting. Or maybe a hardboiled anthropomorphic detective game in the vein of Blacksad. Or what about a dungeon-crawler where the players take on the role of weapons instead of adventurers, magically controlling them to do their bidding, each adventure seeing the players being traded into another adventurer's hands. Ok, that might be a bit silly, but it's a novel idea.
The sky's the limit, I guess.