YouTube served up more than 20 billion video views during the month of October — 49.1% of all 42.6 billion video views on the web during the month. The research was recently published by comScore, which also found that Google and YouTube had a total unique audience of 161 million viewers, nearly three times that of Facebook, which served up the second most video views during the month. Facebook had 59 million unique viewers and 346 million video views. VEVO, the popular music video website, was the No.3 sit...