Idk jgc's opinion but personally this seems like nothing more than a PR move I mean the only thing Kevin seems to be able to do is attract buzz.
If Rose goes into google+ maybe Google wants him as a focus point or part of a public image... these are what I see Kevin Rose as with this but I of course may be wrong.
I don't know however how you got "anyone that hasn't heard of Google has heard of Kevin Rose" from my statement however.