Re: try this:
Good choice. That URL is generated automatically by WordPress, which makes it guaranteed to be as unique as your username. Which matters; bit o'trivia: "URL" means Uniform Resource Locator, and it can apply to anything, not just Web pages. A URL is guaranteed to be unique in this universe, and so they're often used by programmers and in lots of online systems as an identity token.
Domain names are unique, too. "podrock.com" is taken, but "podrock.org" isn't. You ought to pick it up to give yourself an anchor on the Net.