Not sure if this goes for non-healers as well, but this little thingy caught my attention in the Priest section:
Mana will be a bigger consideration for all healers. We aren't trying to make healing more painful; we're trying to make it more fun. When the cost of a spell isn't an issue, then casting the right spell for the job is less of an issue because you might as well just use your most powerful spell all of the time. We are, however, getting rid of the five-second rule, because we don't want to encourage standing around doing nothing. We're also going to cut back on the benefits of buffs such as Replenishment so priests (and all healers) don't feel as penalized when those buffs aren't available.
Especially "...We are, however, getting rid of the five-second rule, because we don't want to encourage standing around doing nothing..." sounds promissing, doesn't it?