Go get DM Updater and root your phone before they push 2.1 to you and you can't anymore
No, seriously, what Chippy said - hit the market and look for stuff that interests you. The biggest difference between the iPhone and Android this the HUGE selection of free apps, go explore them.
After that, go hit the road and try out Google Navigation. If you've never used a GPS before you'll love it, and if you already have a GPS you'll never use it again.
Now, combine the two and make use of some of the awesome free GPS-enabled apps that are out there.