It looks like YouTube has been bitten by the real-time bug too. After the recent real-time overhauls of sites like Facebook and FriendFeed, YouTube is now tinkering with a similar notification feature imaginatively called “YouTube RealTime,” reports TechCrunch.

Much like Facebook’s news feed, YouTube RealTime allows users to track the activities of friends within the site. The feature aggregates actions like comments, online status, and viewing habits, and then broadcasts them to a persistently updated toolbar. So, for instance, if a friend was online watching a video of ACDC performing “Thunderstruck,” you’d receive an update in the YouTube RealTime tool bar letting you know. From the looks of it, the toolbar is being integrated as an omnipresent feature, keeping you updated regardless of where you are on the site.

Although YouTube’s embeddable player has been a boon to viral video, this feature could usher in a new era of engagement for the video portal. Instead of relying on direct interaction between users to spread viral video content, YouTube RealTime could transform common user activities into implicit endorsements. Ideally, this move would promote more exploration within the site, which would also amount to more ad revenue for both YouTube and its partners.

Of course, the real question is how the YouTube community will respond to the feature. Though YouTube will probably offer the option to toggle YouTube Realtime on and off, it’s seems likely that some users won’t want to have their viewing habits broadcast across the service. After all, Facebook experienced a similar backlash when it tried leverage its users’ activities for advertising purposes in its Beacon program.

In the meantime, YouTube will continue to test the feature on a limited basis until its ready for a full launch. We’ve contacted YouTube to get a few more details, so expect an update as more develops.