I’ll point out that trying to increase the time on site may well be at odds with usability
goals, which often are to *decrease* the time that it takes for
visitors to do things.

This obviously applies more to task-based scenarios than more general
advocacy one, but I’ll point out that the vast majority of people come
to most sites with a goal in mind – to find a piece of information, to
make a decision, take an action, etc. Facilitating their goals and
allowing them to quickly do what they’re hoping to do is a good thing.
Having so much great information that they’re compelled to stay and
read can be useful for the right sites, but I certainly don’t think it
should be the key goal of every site.

Overall, most user experience professionals dislike this concept of
“stickiness” – it implies that instead of focusing on what the end
user wants to do, we should try to ensnare them in things that will
keep them on the site. If it’s well done on the right site, a focus
on time-on- site can it can lead to really engaging stuff. But too
strong a focus can lead to clutter in too much cross-promotion,
content that isn’t useful, and if taken too far, user-hostile tricks
that literally make it take longer to do things, hard to leave the
site, etc.

So, basically, like everything else, it depends on what your goals
are. Though, of course, with Neilsen now picking up the banner, it
makes it harder to ignore.

My $0.02


Laura S. Quinn