Call me back when you reach 44% alacrity on a sage / sorc character; which I did a few years ago already.
Back to the present day: alacrity and accuracy will both increase in popularity in 3.0. MinMaxing power / mainstat will still provide big hits, but you risk wasting them if accuracy is low; not to mention things like taunts missing.
Alacrity has always been powerful, kiddies - it's just that now that BW has finally fixed it by making it reduce cooldowns, you'lll see it around more often.
By the way, the changes you'res seeing to off-gcd abilities is surely tied to alacrity changes as well, because (due to lag) fast insta-attacks can get lost in the ether; so the devs are lengthening windows between multiple actions to maximise ability reliability.
I logged a bug with BW years ago and sent them my spec at the time, where I was doing 44% alac on 1.5 second GCD. Their first fix was to make alacirty reduce GCD, now they will make it reduce cooldowns. Finally, it will be the stat they always meant it to be. Took them LONG ENOUGH!