allow people to play as a 'guest'. Think you'll get a lot more people trying it out this way
The "guest" option is a great idea; Even though creating a new account takes about 5 seconds, I know most people hate creating accounts (I am one of them).
I also changed the "Create new account" button to a less intimidating "Play Now!" The "guest" option is still the best idea but it takes longer (I have to change the scipts or otherwise the game would send garbage to the database, trying to auto-save the game).