OK, I preface this by saying I work in research, so I am completely biased.
However, I know first-hand what some of my colleagues, some of the most brilliant people on the planet, could potentially do with them (stem cells), so to be blunt, the fact that the research is hamstrung unnecessarily by politics of irrelevant issues like abortion (irrelevant to this particular issue, not irrelevant in general, I mean) just plain sucks. I personally agree about the removal of partial birth abortion (no medical professional has ever been able to give me one example where this procedure will save a mother's life) mentioned earlier, and with many of the other posts here as well, but this research doesn't have to have anything to do with abortion, as adults have stem cells, there is umbilical harvesting (as mentioned), etc. Christopher Reeve gave an empassioned plea at a conference I was at a couple of years ago advocating this research, and it was a very moving and powerful speech he gave. Unfortunately, millions will suffer until the political hacks from both parties, who don't think for themselves at all, get done arguing about which ridiculous "slippery slope" we are going to slide down, and that is unfortunate, but a fact of life in our 2 party system. I understand the concerns people have, but this research could still be conducted with regulations about the source of the cells, which would allay the fears of clear-thinking people for the most part.