I know this is an old thread, but it's never too late to reply is it ?.. :D
If you have a great site idea / domain name and you want to protect it, that's what I would prefer to do as well, and develop them into something when you get the time.
Originally Posted by Mr.Bill
Where you might consider the other tld's of your domain useless or worthless, there are domain squatters and typo squatters who love to find those tasty available domains they can squeeze a little bit of traffic or value out of.