Reputation is a lousy replacement for page popularity. When Google started to apply their metrics over an entire domain, they already lost a lot of niche information.
Yes, it's better than nothing, but don't expect it to keep the same quality of results we got earlier. Google killed the golden goose when they decided do concentrate their results on the large sites only, and it will be very hard to make similar algorithms work that well again.
Raph now works for Google AFAIA.