Those days are over. With the new stat conversion formulas we now like strenght for DPS. What is strength you ask. It is another stat that increases AP much like agility. Anyway here is a chart I got via ctr+c.
Stats and what they give you. Brackets are raid buffed (+10% stats, +10% AP) values while the normal ones are unbuffed.
All values are assuming HoTW and SoTF. All values are per 1 point of stat
Strength = 2.332 (2.82172) AP
Agility = 1.166 (1.41086 AP), 1% crit per ~78.62 agility (1% crit per ~71.47 agility).
Critical Strike Rating = ~1% crit per 45.91 critical strike rating.
Hit Rating = 1% hit per ~32.79 hit rating [[You need ~9% hit to
become hit capped, so ~295 hit rating total]]
Attack Power = 1.21 AP
Expertise rating = -1% dodge/parry per ~32.79 expertise rating.
Haste rating = 1% haste per ~32.79 haste rating.
Armor penetration rating = 1% armor reduction per ~15.4 armor penetration rating (Source )
I hope you weren't hording agility gems for DPS. While the threads over there can be intense the initial post is a very explanatory and a good read.