I read Danny Sullivan's SEW article on Google Base and I have to agree with him that the concept of contributors being asked to "tag/label" their content seems a step back in time, but I'm not so sure that it is necessarily a bad thing. That's my cataloguing background coming out in me I guess. Maybe it's just a step back to first principles. For some time now Librarians have been urged to "googlize", so it's interesting seeing Google doing some "libraryizing".
Yes, Google could pay attention to metadata standards that libraries have been using for many years to make better use of the intelligent data people are making available in their web pages.