Microsoft just did whatever they wanted with the web "platform", and so will Google.
In Microsoft's case what they wanted was nothing. They weren't a web business, saw it as a threat to their platform leverage, and so just left it abandoned and stagnant for years.
Google is simultaneously better and worse: they won't leave it stagnant because the web is their platform, but on the other hand they have a lot more to gain by abusing control of it.
Edit: well, that and ActiveX, but that's not a good thing...
modern DOM, Ajax, modern CSS, bunch of other small details of JS, all iirc came from IE.