I am a fan of Kathy Sierra, but I have to say that I am not sure about having marketing make the user manuals.
I am more like Darren and keep them away!.
I think what Kathy is really looking for is: Let’s not do a half arsed job on user manuals.
It isn’t about the glossy, it is about giving value.
These days you can buy a rocket system and you will just get a one pager that is barely readable.
It will talk about part X, and you will not be able to find it.
So, if we do care about our ‘passionate users’ let’s help them get their work done (like kathy says) solid manuals (not written by marketing people) are good.
More importantly, beyond that make the thing they are using simple to use, with good help BUILT IN. You know that someone is going to be having an issue in your application, so don’t make them hunt for a manual that they threw away a week ago :)