Congratulations!
I've been recommending this stuff to new Mac'ers lately:
-mail appetizer (
http://www.bronsonbeta.com/mailappetizer/)
show incoming mail messages on transparent window on top of whatever you're doing, awesome!
-backlight 2 (
http://freshsqueeze.com/products/freeware/) to use a screen saver as you background(this is the only thing I'm recommending which is PPC and uses a lot of CPU, but it's just cool to play with not use all the time), checkoff (
http://www.carpeaqua.com/software/checkoff/) menu bar checklist, and mainmenu (
http://www.santasw.com/) are three dank ass menu bar programs
-some keyboard shortcuts:
1) ctrl-optn-apple 8
2) optn-apple 8 to activate, then optn-apple + or - and mouse around
and last but not least, 3) ctrl-apple d while mousing over a word in safari (and elsewere too I think)
Try these all and they'll blow your little mind away. As far as maintenace, all you need to do (in addition to backing up) is to repair permissions before and after any software or security update and run cron scripts (which you can do within mainmenu)
Have fun!