I like the idea of NAP in general, but it includes a lot of hard work. Without 802.1x, it doesn’t make much sense (or i understood something wrong), and 802.1x support for most other network devices isn’t where it should be (an obvious solution is to create seperate segments for printers etc.).

I also don’t see NAP in smaller businesses, just because of the increased complexity – though small businesses are much more often exposed to unpatched, private laptops etc. because of more lax policies, and the fact that these policies are usually not enforced.