...I'd say the odds are pretty slim that apple will provide a beta that could be loaded on via windows
Expecting a beta that can be loaded via Windows is not unreasonable. To my knowledge, every beta OS version released for the 3.0 update could be loaded in a Windows environment without any issues. All "get a mac" knee-jerk comments aside, this is a change from how apple handled beta versions of the OS in the past and therefore is a reasonable expectation.
*Full disclosure - I am a registered developer but use a Windows 7 machine as my primary iTunes library and am very interested in the release of a beta OS 4.0 version that I can install via my primary machine (and more importantly sync and backup via my primary machine as well). Also, I realize I'm using a beta OS that still has issues and such so there's no need to tell me that...again.