to check root, open terminal emulator and type "su". if you get a # prompt, you have root, otherwise it will say access denied or something. if you don't have root, you can just do the adb root method to get root back, at least that worked for me.
if you still have root, superuser permissions likely needs to be reinstalled. you can search xda for su 2.2.2 and download and reinstall it (i think it's a flash file). i've also seen information saying you may need to delete superuser permission data, but i was just able to reflash the app and it ended up working.
if all that fails you can try to nandroid back, or try reflashing again, being sure to wipe/factory reset.