Guitar Hero publisher Activision has just taken another step in its crusade to own every game title with the word "Hero" in it. They've just applied for a trademark for "Sing Hero."

The trademark application, spotted by IGN, is probably for a karaoke game. Obviously filing a trademark is a preliminary step and doesn't mean that a game's actually in development or that it'll definitely use this name. It shows that Activision's got their eye on that particular market, though.

Last week, there was a rumor that eight different Hero games, including DJ Hero, would be released by the end of 2009. If you believe that, than you apparently believe there's no physical limit to how many games Activision can develop simultaneously so what the hell, let's just say this one's coming out in 2009 too.