I know this does NOT work: iMac Core i7 (late 2012) with Windows 7 Bootcamp and 2 external Thunderbold Displays.
Does THIS work? iMac Core i7 (late 2012) with Windows 7 Bootcamp and 2 external Mini DisplayPort Displays?
Nope. Minidisplayport and Thunderbolt work off the same driver in Windows 7 as far as I'm aware, and the driver is garbage. So, if one doesn't work, since MDP and Thunderbolt use exactly the same interface to send video data, the other one won't work either.