I see two groups who will want to be able to respec.
One is the new person who just decides to try the game out, doesn't really pay attention to the stats at first because he doesn't think he'll play it long, then discovers that he's got a truly borked build when he decides that he wants to continue playing. People like that should get one free respec to do it right.
The other group is the min-maxxers. I don't think that min-maxxers should get respecs at all if they are just trying to figure out what will give them 1% extra power.
I see a huge difference between the player that is dabbling for a few hours, then decides he wants to get serious, and the player that is trying to wring every last bit of power out of a build, and wants to change his stats around constantly.
Maybe doing something like one free respec after 10 hours of play, that disappears if you haven't used it by the time you hit 15 hours of play.
Maybe in addition to letting people choose their own allocations at the beginning of the game, the devs could offer a few preset stat allocations, and just name them "General spellcaster", "General warrior", etc. That way, more hardcore people could build their own theory-crafted stat allocations, and more casual minded players could just choose a preset stat allocation that will be good enough for most activities.
