The goal of Xubuntu is to produce an easy to use distribution, based on Ubuntu, using Xfce as the graphical desktop, with a focus on integration, usability and performance, with a particular focus on low memory footprint. The integration in Xubuntu is at a configuration level, a toolkit level, and matching the underlying technology beneath the desktop in Ubuntu. Xubuntu will be built and developed as part of the wider Ubuntu community, based around the ideals and values of Ubuntu.
I just upgraded my laptop to the 8.10 release and will be upgrading my desktop when I am done with this post. To anyone with an older computer that wants to run a Debian-based Linux distro, I recommend giving Xubuntu a shot. I run it on my laptop and desktop which are definately not old or slow computers, but I dislike bloated software that takes a while to run and I do a lot of gaming so I like keeping my computer’s resources free for that and multi-tasking.