Caching dynamic content

A friend who sells networking equipment, software and such tells me that web caching isn't the big thing it used to be. I didn't press for details, and there was a lot of noise in the room, but I believe his take was that with more content being dynamic, caching made less sense. There's no point caching something that's only going to be accessed in that particular form once. I then mused that the AJAX-y interfaces that tend to come along with dynamic content are designed specifically to hide the same latency that caching tries to reduce.

On the other hand, my friend, being in sales, is probably more interested in how much new stuff is selling than how much is actually deployed. It could just be that the market is more saturated than it used to be.

If only I could be bothered to look up the details ...