Earlier this month, Viacom’s supporters came out in force, formally taking the corporation’s side in its legal dispute with YouTube.  Now eBay, Facebook, IAC, and Yahoo have acted to sort of balance the situation, stepping forward to ally themselves with YouTube.

Much as Disney, NBC, and Warner Bros. (along with 11 other organizations) did several weeks ago, the four companies showed their support by filing an amicus curiae ("friend of the court") brief, so this isn’t just a matter of everyone trying to grab headlines in the hope a judge will be swayed by one.

Also, in the brief, eBay, Facebook, IAC, and Yahoo argued that much more than the fate of a single video-sharing site is at stake, stating, "Plaintiffs’ legal arguments, if accepted, would retard the development of the Internet and electronic commerce."

Of course, as we noted last time, judges aren’t supposed to put legal decisions to a vote, and a lot of lawyers have probably already made these points in court.

Still, the YouTube-Viacom lawsuit – which was a huge deal even before this month’s developments – is starting to turn into a legal showdown of epic proportions as more and more parties become involved.

Hat tip goes to Don Jeffrey and David Glovin.