Some interesting behind the scenes thoughts...
My involvement with Google goes back about nine months after they contacted us to see if we wanted to collaborate with them on an initiative to add more scholarly content to the Google indexes. Of course we jumped at the chance, this is undeniably a Good Thing (both for us and the publishers we work with).
and particularly of interest
With our content appearing in the Google indexes it's been interesting to watch the referral traffic increase very nicely. Now that Google Scholar has launched the referrals from the new site similarly jump into life; they must already have attracted a large user base, which isn't that surprising.
Very interesting to hear about a major provider going through a good deal of work - cleaning up of URL syntax, allowing access - just to be sure that they aren't on the losing end of the if you ain't in it, you're gonna be out of it juggernaut.
[UPDATE: Danny Sullivan goes into some of this in much greater detail.]