I was hoping to do this for Super Bowl, but it appears that my Anova sous vide circulator won't be here in time :icon_sad:
My thoughts based on the plan I intended to do:
1) Trim it *very* tightly. The fat cap won't render at sous vide temps, and it's not like you need the fat cap to help retain moisture. And I'd use the flat, rather than a full packer or the point.
2) I'm shooting for the 147 temp for 48 hours. I've read up on it, and it's the temp/time favored by Thomas Keller. My understanding is that certain fats will start to render at 145, but that's below the temp at which the meat starts to shrink and squeeze out all the moisture. Plus, most of the people I'd likely serve it to are not as big fans of medium-rare as I am, so medium is probably better anyway. YMMV, of course, and it's not like I've tried it yet ;-)
3) About 2 hours prior to the end of the cook, I'll likely drop the temp to 130. The only purpose here will be to lower the IT a bit so that when I sear it on the grill, I am less likely to overcook it.
One of my contacts on Google+ has been doing a LOT of smoked SV brisket, and loves the technique. He has a cold smoker setup, so he smokes it at ~150 degrees for a couple hours instead of the 200-225 that those of us with hot smokers can do. But I think we'd be fine either way.
If you get to this experiment before I do, let us know how it goes!