I didn't want to hijack the "what's cooking" thread so I posted this here for you. If you want a good idea of what a smoke ring is, look at this thread:
If your chicken was pink on the outside, that's OK. If it's pink on the inside, that's not good. An instant read themometer will help you determine if your chicken is done or not. The smoke ring is a reaction of the meat to nitrates in the smoke. The reaction stops once the meat reaches 140 degrees. If you want a more distinct smoke ring, be sure the meat's still cold when it goes in the cooker (or use Tender Quick, but that's a different story). That way, it's exposed to the smoke longer before it reaches the temp where smoke ring formation ceases.