This FAQ states that in the near future you may use your very own domain with your WordPress.com blog.
This will come as a nominal yearly cost. This seems good news to me because I want to use my new domain http://www.ajaydsouza.net with this blog. As of now it is just redirected here.
So, I may actually take advantage of this if it is within reasonable limits.
But that will also mean a loss to my current pagerank.
But, would you as a WordPress.com user take this step?