Brian - I'm really thinking you got lucky. Most pork loin is almost completely devoid of any fat at all on the inside. Are you sure you had a loin last time?
Only thing I can think of is that maybe you got the part of the loin that nears the butt, so you got some good marbled pieces in there too.
If you are doing another loin, don't do it like pulled pork. Chances are you'll have a very, very dry and tough piece of meat. I'd take it to 140 max, then take it out. You can marinate or inject it or whatever, but most critical is don't over cook.
If you want pulled pork, a pork shoulder is the easiest cut on earth to bbq and get great results. It will take longer, but nothing is more easy on the smoker. Rub it, put it in a 225-250-ish smoker and let her ride until the meat gets to 195. That will make some amazing pulled pork.
