Curtis M
TVWBB Fan
You don't have to wrap it but you can. It's up to you. There are pros and cons for each technique. As far as smoke the whole time: I am a more is less kind of guy when it comes to smoke. I would throw a few hunks of smoke wood on at the beginning of the cook and not add any more when the smoke is gone. Here and here are a couple articles Chris wrote that will talk about smoke wood early.
Smoke at 250 or so until you reach 160 or the color you like and the wrap 'em... I always prefer to wrap my butts... Put in a foil pan, add some AJ and Rootbeer, foil the top and let her go! Add an additional chimney of lit charcoal, open the vents and away you go!