Any tips or tricks for a newbie to Android? Any recommended downloads, scenes, skins, widgets, apps?

I just got an HTC Inspire, I've had apple for awhile, actually a verry loong time. I'm very tech savvy, so if there's any jail-break like deal for it, please let me know. I know this guy who said he had mario on his Android, how do I get it? Just please tell me all the stuff I should know about Android, thanks!