Almost sure. One of my former techs had a GM background so he usually had a Chevy or Pontiac project car. I saw him working on a rear end during lunch break and asked him what the spindly rear end came out of. He told me it was a 12 bolt and seemed offended that I thought it looked spindly. An 8.8 would have been an upgrade.
Diff cover bolts is what they're referring to.
It would have been better if they had referred to ring gear size like we do, as Blmpkn said there are several variants out there. I always thought the truck 10 bolt was pretty pathetic in that application - I kinda feel the same way about the full size truck 8.8 though. That seems to be the case for a lot of stuff made after the early 80's - bean counters took over.
GM 14 bolt full floaters are awesome in any case, those use to be the go-to axle in the rock crawling world. Shave the bottom, truss the top and that takes care of the ground clearance somewhat.