No problem.
I am sick of people saying "Use the search function!!!", there is nothing wrong with asking questions.
Syncing with iTunes is 100% fine with a hacked iPod.
Best advice for updating the firmware is to wait around a few days - see how it works for other people. It may brick your iPod (although this isn't permanent, you can restore the iPod), even if it doesn't brick others.
Remember, you can still access Mail via the web interface, if you aren't too keen on Jailbreaking.
The experience for me has been fine, I've had no problems. Just remember that all in all, it is a third-party hack, things can go wrong.
Also, be sure to look out for negative problems on your screen when watching movies - like the black on the screen appears negative or something.
And a lot of people are experiencing problems with Safari while playing music. Sometimes it crashes, or the song just randomly stops. This happened to me before I even used Jailbreak

, it's not too big a deal for me, but I just thought I'd mention it.
Enjoy your iPod.