I just compared the 9/27/2010 firmware that has been my regular one, with the new 3/21/2011 on 91W Ku blindscan.
Methodology:
1. Load firmware , locate satellite , then clear all tp's except one active tp. Reboot the stb. Make sure that the single tp is still active, then start the blindscan, FTA only .
9/27/2010 firmware , found 5 channels, 13 tp's in 4:59 .
3/21/2011 firmware , found 5 channels, 13 tp's in 13:47 .
This was a larger difference than I was expecting....