In a nutshell, so I’m told, its ‘bleeding edge‘ which means you get the latest and greatest versions of your favourite applications such as imaging, music ect. At the moment it comes by default with either the Gnome or XFCE desktop although I’m reliably informed you can install KDE.
The reason I started playing with it was the ‘rolling update’ feature and the possibility to ‘roll back’ to a working environment should you or an install reek havoc upon your lovingly nurtured install. As to what its based on for me that’s difficult to answer I have searched the Foresight website and asked one or two on the IRC channel #foresight but have not had a definitive answer such as “Oh its Debian based” I’ll have to do some digging to fully answer this question however it apparently draws on rpath for its inspiration and uses Conary for updating and or adding and removing applications.
I’ll do some more posts when I’ve learnt a bit more.