StumbleUpon, eBay, and Google

Several weeks ago it was announced that eBay was about to acquire StumbleUpon for around 45$ million. Though I have not found any conformation, I am assuming the deal went through. It will be interesting to see what they have planned for the social bookmarking service, as this seems somewhat out of their realm. Perhaps they'll add a section for eBay category interests so users can stumble upon interesting eBay auctions? (It seems others think this is probable.) Or how about letting people receive eBay notifications in their SU inbox?

Right on the heels of eBay, Google added similar functionality to their toolbar, allowing users to receive randomly chosen pages based on their search results. Though I would have much rather seen Google acquire StumbleUpon, I'll be interested in seeing what Google does with this. However, I do have several concerns. How does Google intend to protect user's privacy? Or, on the other hand, is there a way to block "naughty" content, like on SU? Let's say, in theory, that someone borrows your computer and you forget to log off your Google account. They could totally screw up your recommendation profile. In SU, it's all in the user's control. From what I've read so far, this thing's no SU killer. In reality, though, I echo John Battelle. Even if the service does have some quirks and obviously has political motivations, it's always nice to see Google expanding it's "toolbox." (And, if this thing does take off, a little competition can only be a good thing.)