The "Go" button is now smarter, before viewing a page, it tries some capitalization variations. If there is no direct match, it then runs a standard search (with an additional error message stored in "nogomatch" -> Language.php).
I have also changed the default skin to remove the absolute 200 pixel width as there seems to be no need for it. This should stop the Go button from being wrapped into the next line.
Brion, could you update test.wikipedia.org to CVS? I would really like the Go button to be part of the Wikipedia.org default, though. It's mighty useful.
Regards,
Erik