Nothing is set in stone yet, but some plans for the next Ubuntu release, 8.04 LTS, are coming together. You can read the list on the implementation roadmap page.
Here are just few that I think are interesting:
- Automatic bug
- Bugs in Ubuntu are automatically reported online.
- Network file sharing capabilities in the default install.
- Ubuntu Theme for 8.04 - A redesigned theme for Ubuntu.
- Integrate prefetch into Ubuntu - Files are read before they are needed to increase speed.
- Boot Messages
- Boot process messages displayed in Usplash.
- Add user-provided descriptions, feature lists, screenshots and ratings for software in Add/Remove Applications.
- Latest Compiz, a better configuration tool, and exposing keyboard shortcuts in a UI.
Ubuntu 8.04 LTS will be released in April 2008. A draft of the release schedule is available.
Here is a very in-depth analysis of the roadmap.