Would you use a cord bank?
babar: I think the best option right now would be to donate the cord blood to a public blood bank if that option is available in your area.  That doesn't cost you, and it benefits a child more immediately and helps to advance the research.  I think there is a chance of benefit to storing it yourself, but the marketing from these companies seemed to be preying on parents' sense of guilt so much that it was off-putting to me.  I can put those thousands of dollars to better use to benefit my children.  Of course, if the money isn't a meaningful amount to you, your decision process may be different.