N8x0s are not that closed in that respect, and there are other distributions working fine on them. It's just that there's not enough developer critical mass to polish them (again, the hardware is 6 years old and there are shinier toys available all over the place).
I don't want to mirror the repositories but I do want to make sure all the packages I've installed are available in case my device needs to be restored. So here are a couple scripts for anyone who wants to backup their installed packages. http://maemo.qzx.com/#backup_repos