I was considering banking the blood, or donating it, but in order to "harvest" it, they have to cut the cord early (or normally, as they do in hospitals), before it's stopped pulsing so that the blood can be "milked" from the cord and placenta. I'm planning on leaving the cord attached until it's done pumping and the placenta detaches on it's own, instead of having it yanked out. This would empty the cord and make banking pointless.
Aparently if you birth in a hospital, and probably some birth centers, they "milk" the cord and take the blood, if you don't tell them you want it before hand. And it's used for stem cell research, or whatever they choose to do with it. It's one of those forms you sign off on when you're admitted. Giving them your "cast off" fluids and "parts".
edit: just skimmed the newborn screening stuff: no way. too interventionist for me.