Thanks for the great thread, I'm learning about my new N810 every day. In hunting for the extras-devel, I wound up finding a super-easy way of getting it loaded. I went to http://wiki.maemo.org/Extras and clicked on "To enable Extras repository, just open this link on your tablet.", then further down the page, I clicked on another link to enable the extras-devel repository.

Thanks to Maemo for making it mega-simple! I'm now looking forward to installing Abiword and taking it for a test drive.