Root Just got my N1..few questions

Just bought an N1 off craigslist. Im using it on att, and i know i only get edge an thats fine with me. Everything works 100% im only worried about the OTA updates.

I did a full factory reset and it still says im running...CyanogenMod-6.1.0-RCN-N1....doesnt this mean im rooted and wont recieve updates OTA?

I thought the factory reset would have fixed this. Sorry if its a stupid question. Im not sure if thats how all N1s come or what.