Gaming channel Machinima captured the #2 spot for the first time in July with 25.3 million viewers, according to comScore.
Video music channel Vevo remained the undisputed number one with 43.9 million viewers. Warner Music was at number three with 24.9 million, followed by Maker Studios with 20.4 million.
Among the top 10 YouTube partners, Machinima demonstrated the highest engagement (83 minutes per viewer), followed by Maker Studios (45 minutes per viewer). Vevo streamed the greatest number of videos (571 million), followed by Machinima (564 million).
The comScore Video Metrix service shows that more than 184 million US internet users watched 36.9 billion online content videos in July, while video ad views totaled 9.6 billion.
Google sites, driven primarily by video viewing at YouTube.com, ranked as the top online video content property in July with 157 million unique viewers, followed by Facebook.com with 53 million, Yahoo! sites with 48.7 million, Vevo with 44.8 million and Microsoft sites with 42.7 million.
Nearly 36.9 billion video content views occurred during the month, with Google sites generating the highest number at 19.6 billion, followed by AOL, Inc. with 665 million. Google Sites had the highest average engagement among the top ten properties.
Other notable findings from July 2012 include: 85.5% of the US internet audience viewed online video. The duration of the average online content video was 6.7 minutes, while the average online video ad was 0.4 minutes. Video ads accounted for 20.7% of all videos viewed and 1.6% of all minutes spent viewing video online.