This community is not a part of Canonical, and is not an official Ubuntu thing. Think of it as a fansite. Granted, if we worked it out with Canonical, we might get them to give us that subdomain of their website, but if we are independent of them, that's not really necessary.
And that's part of the wonder of Ubuntu and all Free Software -- anybody can do anything independently. Canonical manages Ubuntu, but they don't own it -- and if you want to start "BetterUbuntu.com" and sell people copies of Ubuntu with a few small tweaks, you could go ahead and do that. Or if you wanted to actually start a real branch, like Kubuntu, you could do that too. Or you could start a community site like this. Or you could just start distributing Ubuntu as is (except with different branding, because Canonical has a few trademarks), yourself, and try to get recognized as the new authority in the Ubuntu community -- although the community is pretty close to Canonical, at this point.