Hwang Woo Suk is a liar.
There was at least one honest research group, with very promising results, that was shut down 5 years ago, becuase of his lies. They (the people doing the funding) figured that he was so far ahead, that it was pointless for them to continue.
http://www.timesonline.co.uk/article/0,,25689-1958050,00.html
Luckily this type of behavior is probably only representative of 1% or so of scientists.

---Al