IP Camera as a viable security camera alternative ?

There is an ongoing discussion thread on IP camera. I saw some good
discussions about security system installers putting IP cameras in
shops. I checked out the web site shown in the discussion thread. It
seems that all the functions needed for a typical shop are all there
(motion detection, video recording, video output to quad processor and
monitor, ...). The video quality also looks good. Based on the price
given on the company's web site, I can put together a system with four
cameras that cost $400 instead of the $1000 or so that I am buying now
for four cameras, video capture card, and software. Also, there is no
wiring issue, no hardware board installation issue. ...

Am I missing something? Is the IP camera replacing the traditional
camera/video capture card approach? Is it better for us to recommend
our customer to go with the IP camera approach?