To answer your questions there was a good thick layer of fat on the topside of the meat but the bottom side only had moderate marbling. I never would have thought to cook a beef shoulder until I watched a BBQ university program on PBS where the host cooked a massive beef shoulder called a clod (18 lbs) I actually was going to buy a brisket but could only find flat cuts at most of the stores so as a last ditch effort I went to the wholesale club and found this beef shoulder and decided to give it a try. There was several nice thick lines of fat running through the middle of the meat but was fairly lean with light marbling otherwise. Despite this, the meat turned out wonderfully tender and was not the least bit dry. I smoked the meat between 220-240 degrees for about 5 hours and then allowed another 5 hours without smoke (internal temp @170 before resting...Next time I will pull it at 160 to get a more medium temp)
The best beer to drink while waiting is simply the "ICE COLD" variety (although I was personally drinking Blue Moon Ale) Like I said before the ole' gal was not too happy to kiss me since I smelled of smoke and beer most of the day but that didn't matter since my mind was on the food and cold beer.
As for the Cherry Chipolte seasoning, it was a dry rub I applied to the cut up whole chicken which brined overnight. I picked up the rub at BBQ's galore (John Henry's Brand.) It was great!
Here is the link to some of the rubs