Like I said, nVidia didn't have a hard date for rollout of the 305.xx driver. The 21st is now the most likely date, assuming nothing else in QA goes wrong, and that driver will unify the GTX 660 Ti's codebase with the bulk unified driver, as well as merging the INF file. Expect it on the 21st or before, again barring any last second issues.
The driver includes optimizations for shader processing in GW2, some fixes for active sprites, a major fix for texture mapping and another huge fix for active DX9 memory spooling (it currently is adding too many threads to the memory pool, and spooler isn't pushing them to the GTE fast enough, which is resulting in choppy performance)
Once that driver hits, it will fix the above, which should be a major boon to you Fermi and Kepler users. GT200 users will see a decent increase as well, particularly with the spooler to GTE fix.