Kindly see the full picture.
Google Chrome OS will require a huge distribution & partner echo-system.It's various other initiatives [ like green initiatives (power-meter etc.) ] to counter the giants cannot be handled in-house.
Google Ventures, in my opinion, is a wise move to influence budding entrepreneurs in creating this eco-system in the shortest possible time to counter giants like Microsoft.
sample this :(here's what GV says)
"We're studying a broad range of industries, including consumer Internet, software, hardware, clean-tech, bio-tech and health care"
"You don't have to be a potential Google acquisition for us to want to work with you; we're out to build great companies"
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In my opinion it translates to:
a) Hey! we'll teach you how to develop clean-tech,bio-tech & health care solutions on top of Chrome.then we'll acquire you
b)Hey! Chrome is the next reality, so if you are a software,hardware,internet vendor, we have some very special margins to dole out.Jump in!!
Having said that, i believe that it is a win-win proposition for start-ups as well as GV.Let the battle begin!