The good things about the HD3 chip is that it reduces the price of DLPs and that it goes darker and is smaller than the HD2 chip. I beleieve that it also has an extra segment on the color wheel. The consensus, however, is that the HD2+ chip is the jewel in TI's crown at the moment, so far as contrast goes and distinct resolution. The HD3 chip wobulates to 1280x720 from 640x720, thus explaining the reduction in size and price. I'll leave it up to individuals about whether they can see the difference between the wobulators and the true 1280x720s. The HD4 chip wobulates 1920x1080p using half the horizontal resolution. I haven't seen enough of them yet, but I'm not sold that this type of chip will look as good as DLPs, LCDs, or LCoSs that have the full complement of pixels.