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3 of 4 The rabbit hole goes deeper; added 45 characters in body

I'm all for opening up oneboxing, but not for creating yet another standard.

There are already several competing standards for onebox-like functionality and semantic representation of web page data:

If Stack Exchange is going to do this, they should adopt one of those instead of re-inventing the wheel. My preference is for oEmbed, with a secondary preference of Open Graph.

Fortunately, the charging one has been solved now that we've all standardized on mini-USB. Or is it micro-USB? Shoot.

Note 1: what you're proposing is pretty close to Open Graph anyway.