I realize this. But I fear that most of the people complaining are themselves missing a few details. Just because a company owns the rights to a game's brand name does NOT mean they'll instantly put a stop to all mods for it. Take a look at Counter-Strike, Team Fortress, and Left 4 Dead. Valve not only allows mods to spring up but friggin' SUPPORTS them. Hell, they even add some of the better mods into official releases and updates. My point is, people are afraid that the "community" won't be able to contribute, add to, or mod DotA 2. If anyone had bothered to read Valve's announcement, they'd immediately realize that DotA 2 is being designed with contributing and modding in mind. The whole basis of Valve's version of the game is to create a friendlier, more open community for a game that desperately needs it. Let's face it, DotA at this point only really caters to those that are hardcore players of the game. New players really don't stand a chance and are often reviled and met with fervent hatred. Valve plans to rectify that. If that means they have to copyright the name, I'm all for it. I'd say the same if Blizzard had decided to do it. I just feel like it's better to have a professional company make the core product first, and have the community contribute and modify it afterward.
[edit] I'll be honest though. I'm not really concerned. I was never a big fan of Dota. Maybe it's because of the community, I don't know. All I know is, this whole thing is getting out of hand and misinformation is more abundant than the truth. From all parties involved. So, until this thing simmers down, I'm just not going to care.