People who like to see at a glance where a bookmark goes often care. Bad titles are one thing, but not even knowing what's at the other end of the link is really irritating. Likewise, it's nice if you use browser tabs.

It's so simple to add a favicon and the branding payoff is immediate -- why wouldn't you? Most of the large community sites I've worked on or with have benefited from this trivial change far out of proportion to the 90 seconds it took to Gimp a photo/logo down to size.

As the article says, it is not about pleasing non-geeks. It's about helping them find your site again, for instance in your bookmarks. Someone who genuinely don't care about favicon probably never open many tabs at once, nor uses bookmarks, nor search his browsing history.

It is possible however, that almost nobody knowingly care about favicons. But how many will miss it if you deactivate them? I think this would be far more than just developers and internet addicts.