I've been working with NBC's Sports Programming and their scheduling for well over a decade now, and this is the first time I can recall NBC actually telling their affiliates anything close to this detail regarding future sports broadcasts.
328 NBC Sports events and specials in 2010 alone! Just between us, if we tried to track how many times each of these events were to be changed/moved/canceled/etc in the next year, I would raise my rates. So, let's pretend all of these will air on the dates NBC claims now. :)
My five NBC RDRx clients will see this massive announcement showing up in MediaOffic inventory and estimates over the next several days, because I do understand the value of presenting annuals with hundreds of sports event sponsorship possibilities all at once. Perhaps this lump disclosure by NBC is their effort to join in that team effort.