What does the release of the 2.1 HTC Kernal mean for me?

[ToxicToastKatz]

ok guys/gals....so I have been debating rooting and using Fresh 1.1 and was possibly going to do it over lunch today at work, however, i have a question:

With HTC releasing the kernal for 2.1 for the Hero today, what does this mean for me (the unrooted Hero user looking forward to 2.1)?

Is it any indication as to the update being released soon? I know the 99.9% answer to that is "it's up to Sprint to release it" and the 100% answer to that question is "your guess is as good as mine", but historically speaking, when the kernal for a build is released, what timeframe usually exists between kernal release and upgrade release? I guess the bigger question is, what exactly is a "kernal"?

I know most everyone is going to say "root, once 2.1 is released, the cooks will have the rooted version available shortly after" or "root, and if it does come out, you can always flash back the stock RUU and upgrade OTA then", but the think is, I dont' want to root and then with my luck, 2.1 gets released next week

Just looking for some insight/best guesses.

Also, while on rooting, I actually brought a separate microSD card to make the Nandroid backup on. Is this a good/bad idea? Is the best way to do this to make a copy of the SD card on the PC, do the root and flash with a clean card) and then copy everything back to the card? I have an 8 GB card that is nearly full. Don't know how much space is required on the card to root/flash.