Wrath came along and in present day its pretty much the same without the worry of running out of mana. (If you have plenty of replenishments)
We base all our gemming through maximizing our throughtput.
I never see people in high end progression gem intellect anymore.
One thing that dissapointed me the most was the removal of mana potting on CD.
I quite enjoyed having to worry about my mana and hoping my next mana pot came off CD before I became oom.
Anyone remember the good ole' Alchemist Stone?
I swear I used that thing forever just to get more mana return out of my Pots in TBC.