There are several improvements in 8.10 that won't be available to 8.04. First
there is the guest account which allows you to have someone use your computer as
a guest without having access to your files or system. Secondly there are two
new applets. One allows you to clean your system of orphaned files. The other
allows you to install Ubuntu to as usb device similar to Unetbootin. Thirdly
there are improvements such as the latest kernel 2.6.27, more drivers, improved
networking including pervasive internet, latest Xorg 7.4, Gnome 2.24 (also
available for 8.04), and Samba 3.2, encrypted private directories, and last but
not least dynamic kernel module support which is supposed to reduce kernel
compiling as new drivers come out.

In addition it loads faster and shuts down much faster.