A game site I used to frequent. I always thought that this would scupper new word-of-mouth visitors.

http://ntsc-uk.com/

http://www.ntsc-uk.com/

I am unsure if this is intrinsically stupid, but in our university, we have subdomains of the form www.faculty.university.de, mail.faculty.university.de, ssh-gate.faculty.university.de, mayflower.servers.faculty.university.de and so on. At least the ssh-gate is different from the www-server, and it appears the www-server is equal to the mail-server. Stripping the www here would be a world of hurt.

Long story short: the www is not necessarily stupid, especially if you use it to designate a web server from different servers.

there is absolutely nothing preventing them from still using subdomains while making the domain itself resolve to something useful.

For example:

http://pullmantransit.com/

http://www.pullmantransit.com/

Probably Apache defaulting to the first virtual host.

So let it be the browser's responsibility to try both with and without it. They'll either be the same, or one will be nonexistent or a not-found page; it's not like people put one site at www.x and another at x.

You would hope so, but unfortunately you'd be wrong - a tiny fraction of the time, but still...

Well that would seriously increase http requests and dns lookups which slows down everything.