I really think you should add the Go button.

If Microsofts usability testing decided that it was worth putting in (and when you have seen newbies trying to surf the web you'll agree) then it really does belong.
Just make sure it can be turned off (best of both worlds).

I assume you are targeting the ordinary user, especially with your questionable choice of using the microsoft Favorites (which for all no American english speakers is spelt wrong, and theres nothing we can do about it).
I always thought bookmarks were a far cleverer metaphor, and Microsoft would have used them if they had not been at risk of infringing copyright.
Also, with Netscapes impementation of bookmarks you dont get all the Advertising just about every program dumps into your Favorites folder, and you can link to it as a web page and easily browse/search through your own book marks.

Hope you take this into consideration

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Think different, use adverbs proper

Actually, I think that's one thing they're working on. I seem to remember seeing a request with an 'ok' reply.

Also, I think it was going to be blue instead of the IE green go button. Which is good. I like blue.