There's also the huge raft of legacy but useful support sites, the quite active forums, the wiki ...

aaaaauuuurrrrgh that's sound in principle but placing 301 on a domain like that is really, really bad.

Agreed, but in this case those reasons actually make it more valid, because there will be no way for someone else to reverse the decision once it is made.

It closes the door on some zombie resurrection of openoffice and essentially cedes the identifier to libreoffice.

301 redirects are the herpes of the Internet.

You make one mistake, and it's with you for the rest of eternity.

Oh shit, thanks, I had just set up a 301 redirect on my personal page this morning when I meant to use a 302, your post made me realize the mistake.

I was sure it was the other way around 301->temporary, 302->permanent.

GitHub Pages sends 301 redirects when you put a CNAME file on the repo. That's insane.

Indeed, it should be 307 instead, just to keep the decision revertible.

As 'jacquesm points out, you may want to explicitly make the decision non-revertible in cases like this.

Why is that? What if you want to change your domain name?