digital performer ? abletons is easy and ok ... i guess the ones radio mentioned blows fl and live out of the water. someone recently mentioned dp has the best algo .
FL also uses elastique code, lots of versions in the sampler for example and i also think in the playlist.
test Reaper ones there are a bunch, you can choose algorithms which show better results dependent on audio material or effect you are after I've heard rumors that Melodyne's are top notch
for me, Reaper has wide range to choose from, and easily accessible - either Alt+drag items, or draw stretch markers and take pitch envelopes
I'll go out on a limb and say Paul Nasca's PaulStretch algorithm. Available as a free of charge app here.
Most accurate? It's not a DAW, it's a plugin. Serato's Pitch n Time, and its not even close. Second one (a freebie) is PaulStrech's plugin as well.
Ummh, I don't think PaulStretch and "accurate" belong in the same sentence unless a lot has happened. Wasn't it designed to do extreme timestretches like 1000x stretch factor and so on? It's great for sure, I use it to create pads from guitar stabs, and stretching short string quartet pieces to hour long ambient soundtracks for my evening walks.
Now known as Adobe Audition, or the stripped down version Adobe Soundbooth for people who find Audition(CoolEdit Pro) too complicated... Cooledit Pro 2.1 runs fine as a 32bit app in 64 bit windows 7. I use it on a couple of computers,its fast for cutting up samples among other things.