Hi,
I just tested this on my local machine and it didn't work, but after making one small change it did work, so this will be fixed in the next release.
To clarify what wasn't working was using the searchInput control in the layout.master page, it just redirects to the search results page passing the search term in the query string but the google search was not picking up that query string so it was only working if you enter the search term after going to the search results page. Now with the fix it will pickup the search term from the query string and execute the search.
Until the next release the best solution is just to use the search link rather than the search input, ie set LinkOnly="true" on the <portal:SearchInput control
then after the next release (sometime later this month) you can remove that and go with the search input box.
Best,
Joe