The google plus games are gadgets!!!!
Proof: Go to the games tab, choose a game and right click on the game and choose open frame source (or whatever it is called in your favorite browser).
Part of the url to the iframe:
A brief look at the code (which by the way is not obfuscated, it even have nice linebreakts) indicates new google plus APIs.

I am getting curious, hard to wait for official anouncement before poking around more. ;-)
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