If you are thinking about going to DNS12-Medical after it comes out, being on a 64bit OS and having a minimum of 4G RAM is recommended to run their best algorithms.
Indy, some talk about Dragon 12 being able to use multiple processor CPUs more effectively, increasing accuracy & speed "by 20%". Same thing as they said for version 11, but I found the incremental changes were, well, hard to perceive (to put it kindly). Did you get any impression that this was more than sales fluff with version 12?
I feel the need for speed...