There are a few projects for getting Debian onto Maemo tablets. Here are the currently active ones.

Easy Debian is focused on running Debian applications in a chroot.

Maemo on Debian plans to replace the Maemo 5 with a up to date Debian base system and to port the existing free and non-free Maemo5 packages to this new base.

The Debian pkg-n900 or elektranox project aims to get standard Debian running on the Nokia N900, and to contribute the necessary updates to Debian. See the kernel status, a summary of the ongoing effort to upstream N900 kernel patches (also here) into the mainline kernel. See also the screenshots, blog and natisbad.

The Deblet project (now apparently discontinued) was focussed on bringing bootable Debian to the tablets, using an installer system that bootstraps a complete Debian system through the use of packages and a local repository.

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