Maybe. Anyway, some news. Uplinger posted the following on the WCG forums:

Quote Originally Posted by Uplinger
HCC does not send out the same exact work unit to both windows and linux. It is as Randzo says, when the first work unit in the quorum is picked up, the OS is set for the wingman. This means linux compares with linux. Windows compares with windows....

A batch consists of about 1500 work units, these work units are split between all the OS's, so there is no discrimination based on batch level.

-Uplinger
Don't know what to make of that really.. So they are the same, and yet they aren't?