I was really taken with this approach as it is really quite elegant and simple, yet a potentially really useful tool if you're required to prioritise where you direct your time and resources.
The focus is mainly on technical development, but as some of the examples illustrate, the principles apply to things like website copy writing too.
Author Jared Spool says:
Working with our clients, we've seen teams prioritize their work using the Kano Model. They're constantly monitoring their users' current basic expectations, to make sure there's nothing they're missing. They are always on the lookout for inexpensive ways to add excitement generators. And they use the performance payoff to help understand how much delight they can generate with new features.
The model becomes a great way to explain to stakeholders and project owners how to tackle hard decisions. It's a great way to keep teams focused on the right priorities.
Understanding the Kano Model: A Tool for Sophisticated Designers - article by Jared M. Spool
This idea of delightful design is also covered with lots of examples at Cooper.com:
Passive magic, design of delightful experience - blog post by Stefan Klocek