From what I see, you're probably smoking a single skinless breast (otherwise you would just follow the turkey breast recipes)?
A boneless breast will greatly benefit from a brine. Then, rub and wrap in bacon to help retain moisture. Also, with skinless turkey or chicken, use a water pan. I normally don't for whole birds (the skin is a barrier to moisture, just like ours), but skinless is a different matter.
Here's my version of a basic poultry brine:
http://smokinitforums.com/index.php?topic=1447.0
For boneless breasts, I'd brine no longer than 3-4 hours. Then, rinse well, rub and wrap in bacon. Smoke with cherry (2 oz.) until 165 internal temp. Should be the ticket!