Okay, this is not an official release and should not be flashed on to your phone unless you know what your doing.
This can brick your phone and will void your warranty.
Having said this - It is my opinoin that if you need to ask what this is then you should be using this.
I have rooted my hone and put the recovery image on my device. Then I restored the 2.1 rom onto my device using nandroid.
I liked this image - I didn't have any problems worth mentioning. The rom is being
discussed here.
Just an FYI - I used SirPsycoS recovery and Greeks 2.1 rom, I went from 2.0.1 to 2.1 and back to 2.0.1. I just flashed back (recovered) to 2.1 which I'm going to try and run for the rest of toda.