For those who are stating that the pre-painted plastic will be both high quality material, and high quality paint, I personally don't share your enthusiasm.
While, yes, for a LOT of people who play D&D, pre-painted would be a god send, it leaves the other end of the crowd out in the cold. I can't fathom why the hobbyists would be treated like a scourge because they like both metal, and to paint things the way they see fit.
I like doing custom colors. I couldn't imagine letting someone else paint a character model for me, but I do completely concede that such worries are my own alone. So why not do both metal casts, which are more expensive (I don't mind paying extra for mulit-part metals), and plastic pre paints for folks who just want to jump into the game without a hassle?
I refuse to buy low quality plastics like this. I don't care how utterly great a carver is, you will NOT get the same detail with plastic that you do with metals. Even with the high quality hard plastics from Games Workshop, you will notice places where the mold has lost detail. Be it on ears, on facial features, on belts, or otherwise, the quality is sub-standard compared to metals.
Also, remember that the pre-painted miniatures are going to have some 'group identifying' factor on them. Bright blue bands on their arms, legs, or even hair, or bright red for the opposite side. The rumors are that this is a collectable game, remember.. Now you have to ask yourself: Do you really want your Gnome fighter to have blue hair/arm-bands/boots?
I don't play wargames myself. I have so little time free as it is, and that is dedicated to D&D. I would rather side step the stupidity of trying to buy boxes and boxes of say.. Dwarves, just to try and get a Stone Giant model. I wan't the damn stone giant, just let me buy it already. Especially since I buy miniatures maybe once every 4 months (I just don't have time to go to a store so far away to comb through box after box of Gawd forsaken dwarves in hopes that I'll get a giant that is 'rare'). I'm sure a lot of people here are driven right up the wall hearing rumors that this indeed might be a collectable game.
Finally, and yes I realize my reply is a random mess

, Don't be fooled into thinking that the plastics in this line will be anything like the hard plastics of the GW line. They will be more like those horrid things from Mage Knight. You know, the rubber that makes a bent sword bent for all eternity? It costs a massive amount of money to do die-cast, which I believe the GW hard plastics are. It also costs a monilithic amount to use that grade of material, but GW makes that back due to sheer volume, and pricing on their alternate products. I'm pretty sure WOTC won't be dropping that many dimes into miniatures again.