Every one of those links referencing downloads.maemo.nokia.com result in permissions denied (403) errors (just click 'em and see for yourself). It appears Nokia has gone beyond simply ignoring N900 owners and is now outwardly cutting off support for devices that are still under warranty! (mine is only a few months old!)

Has anyone got a mirror?
I was considering a reflash, but without the SSU repositories, I'd never be able to bring it up to even a basic stable state.