The way I usually get my vote info is based on whether it's a rout or close. So when Nas won, it was a clear cut rout - the other albums didn't come close. With Tyler v Nas it wasn't a rout, it was (relatively) close.
Going back to Beyonce right quick, a good way to think about the big awards is it basically boils down to coalition voting. If a good R&B album gets nominated for AOTY, the vast majority of R&B voters will vote for that album. From there it's just a question of what the other voters will do (who do the rock voters vote for, who do the pop voters vote for, etc). While both the Beyonce and Adele are not nominated in the R&B album categories from what I understand there are plenty of more traditionalist/conservative R&B voters who simply fukk with Adele more. Not just white R&B voters, I'm talking about black voters as well. Point being if Beyonce doesn't win enough of the voters who you'd expect to support an R&B artist's album for AOTY then she could be in trouble. Now to be fair the flip side of that argument is that there are plenty of pop voters who will support Beyonce over Adele, so maybe it evens out.
I still think the wildcard is ABBA. If you pull up a list of past AOTY winners you'll see quite a few legacy artists winning for their new album, whether the album was truly good or not. I don't expect ABBA to win obviously but it's worth keeping in mind.