Much smaller, I don't think. It will still have to grab the screen and render directly onto it. It's basically the same thing a regular plugin would do except a little bit of identity validation, from what I understand.

Technically speaking it's almost the same as the status quo, but a little bit of DRM principles have now been enshrined in the foundations of our web. Depending on what your view of DRM is, of course, this is good news or bad news; but from a technical point of view, it changes very, very little.