The site is for questions that can be answered. Not gripes (or praise) about the new releases.
If you have an issue that can be asked in a question format (that isn't super-subjective, rhetorical, etc -- eg a question that can have "one best answer"), we welcome it. Otherwise it's our job to make sure people who need help get it. Closing random discussions is part of that.
Coincidentally, if you don't like Unity, you can select Classic Ubuntu from the login screen which will give you a similar experience to Ubuntu 10.10.
Edit I should go on to clarify that any topic (not just Unity) is a candidate for closure if it can't be sensibly answered. This is by no means a conspiracy to protect Unity or to shield its developers from criticism.