Regarding the questions of whether Agi will once again become better for us than comparable ivalues of AP, I investigated with some of the gear available in the sheet. I'm not claiming this solves the argument entirely or is even a particularly scientific approach to the problem, but these are my results.
This is for BM (54/17, but I doubt a few points here or there would dramatically change it). I didn't check for Marks and we already know agi is better than AP for survival. I used the "Level 80 Raid" buff set that comes with the sheet, and a Raptor pet. Again, I'm just looking for a trend here, so I'm not concerned about getting everything 100% kosher.
I selected what seems like a fairly representative sample of good 5-man/heroic gear. For reference, this left me with:
1428 Agi
2880 AP
630 Crit
284 Hit
80 ArP
94 Haste
At these levels, Agi is .788 DPS per item budget and AP is .859. So AP is about 9% better than agi.
Next I picked 10-man gear. This brings the stats up to
1526 Agi
2772 AP
673 Crit
299 Hit
126 ArP
156 Haste
At these levels, Agi is .858 DPS per item budget and AP is .921. So AP is 7.3% better.
Finally I picked 25-man gear. I pretty much just picked the top of everything in the gear planner.
1530 Agi
3146 AP
824 Crit
299 Hit
136 ArP
275 Haste
At this gear level, Agi is .901 DPS per item budget and AP is .952. So AP is 5.7% better.
So, with each gear increase, as AP continues to rise, agi becomes more valuable, just as we've come to expect in BC. I'm not going to speculate on what our future gear will look like exactly, but it seems pretty likely that in a tier or two we'll be back to 1 agi > 2 AP - at least in terms of what the spreadsheet says values are.
