How Google Rank Videos
Google have recently revealed the basics of the algorithm that determine where videos appear in the google video Top 100.
From the google blog it seems that a videos popularity is figured out by looking at how many views it has had combined with how quickly it got those views.
Google have also made public the list it has been using internally to show what videos are most popular in different countries.
Unlike the regular search algorithm this algorithm is impossible (maybe not impossible) to manipulate, So it raises the question, In the future will google implement a similar system for their search algorithm.
Related link The best of google video and youtube