Just saying "stem cells" is highly inaccurate.

Adult stem cells - those taken from a person's own body, multiplied, and reinserted in the appropriate location - have yielded more than 90 cures/treatments for diseases and serious medical conditions to date. In fact, a dear friend of mine just had a blood cancer put into remission when the doctors at Stanford replaced his marrow with his own stem cells.

The two people that have received a benefit from this EMBRYONIC stem cell transplant (It is a transplant - because it's someone else's tissue) are the most recent in a long list of experiments using hESCs that have failed miserably. Most develop tumors. Scientists have just spent so much time refusing to bow to ethical concerns to evaluate and conclude that hESCs have extremely limited usefulness.

Given their near-perfect failure rate, I don't hold out much hope that the patients in this study will experience everything they want long term. Meanwhile, entire organs are being regrown using adult stem cells.