I've never been to Oli's Thai, but having read Tony Naylor's rundown of the best ten budget restaurants and cafes in Oxford, it's leapt right to the top of my "must try" list. The description of the pork belly alone had me marinating in my own drool. I've also never eaten at Big Society or Dosa Park (the latter because, as Naylor suggests, it hardly looks like the most salubrious of eateries). Nice to see worthy mentions for the Covered Market and Atomic Burger, as well as Door 74, the restaurant run by an acquaintance from the football field.
Needless to say, Naylor's article provoked plenty of reaction from others as to what was included or excluded. Here's Stephen Tuohy of Smash Disco's alternative list.
(Thanks to Ronan and Matt for the links.)