Google-owned YouTube accounted for the majority of the more than one-third of all 9.8 billion videos watched online in January, as measured by comScore Video Metrix service and reported on Friday. More accurately, the 3.36 billion video views amounted to 34.3 percent of the total, far outpacing the next-highest, Fox Interactive Media’s MySpace, at 6.0 percent. This marks a 1.7 percent improvement over December 2007 results, where a record 10.1 billion videos were viewed.

Google’s sister company also gathered the most viewers, at 80 million, out of a total of over 139 million U.S. Internet users. Fox Interactive was again second, at 53.9 million viewers. Apple was at the bottom of the top-ten list, with 8.7 million.

YouTube also held its viewers’ attention the longest, with an average 109.9 minutes spent watching video per user. Fox viewers spent just 11.7 minutes on average, while Viacom viewers were second-best at keeping their attention on the content at a 33-minute average. Apples viewers averaged 21.2 minutes each.

The comScore findings also revealed that over three quarter (75.7 percent) of U.S. Internet users viewed online video in 2008, with the average user accessing 70 videos.