For the last few days, CyanogenMod 7 got released this week, you can read all about the changes and how to install it on the linked thread. I have decided to write a quick entry with all the useful links for a nice experience with cm7.

I would advise to take a look at the nightlies. You can also take a look at the dedicated sgs2 forum. Also, you might want to change your radio file with another than the shipped one, in which case, take a look at this page. Last but not least, here is the nightly changelog.