I've had similar thoughts, albeit only for Google's sites. I would imagine this would be something more likely to be seen through Chrome (or even the Chromium OS).<p>My gut reaction is that most people wouldn't want Google on top of every other site they visit. Of course, I'm also amazed at how many toolbars I have seen people install and run concurrently in IE, so I could easily be wrong.
Personally I disagree. Maybe as options, but not by default. The bar looks nice because of its simplicity.<p>Adding a bunch of addon attachments would ruin the unobtrusive functional aesthetic that i think that google is going for.