Who knows what the Jan Yorkfields will bring... however according to Intel they'll be releasing X48 by the end of the year, which supports 1600MHz FSB. If the Jan. Yorkfields dont support the 1600FSB, then Intel will have a 1600FSB chipset without 1600FSB processors for half a year, until Nehalem shows its face, which seems like an unlikely move on Intel's part. So if you're asking my guess, I would say January Yorkfield will support 1600MHz FSB to match the 1600MHz DDR3 support and 1600MHz FSB on the X48 platform.
The p965 chipset "can" support the Yorkfield @ 1333mhz
The Asus P5B Deluxe for example will overclock from 1066 to 1333 and run a Yorkfield with a BIOS update.
Your P35C is newer than the p965 and should not have any trouble.