doc_z - 9:56 am on Apr 9, 2012 (gmt 0)
I'm sure that Google will detect algorithmically fake ratings in the future.
However, so far it seems that every kind of manipulation works. I've seen sites just with microdata but no rating option as well as sites starting with showing "2456 ratings" for an entry. So far Google seems to ignore this problem - all these sites are still showing rating data.