Yes, the performance hits, in spots, is actually severe (I believe Anandtech has a story on it) and the system I demo'ed it on had a dual-core 4400/x1900xtx/2 gigs of fast RAM and it was pretty apparent that the technology and/or implementation isn't there yet.
Tha said, I think that if the company can last long enough, we'll get some amazing games, but we're a long way from a. games that requires the card (e.g. Cell Factor) and b. it being cost-effective for the end-user to purchase which will lead to more of 'a'...ye ol' chicken and egg, *sigh*.
In the article mentioned at post #20, price of $250 mentioned...also mentioned that BFG was going to offer a card, ASUS also...and Nvidia has cooked up a deal with physics middleware develeper Havok ...