The upgrades since 9.10 are done in these fields:
If you want to upgrade your Ubuntu 9.10 system then simply type
- Linux kernel 2.6.32
- KDE SC 4.4
- Major new version of likewise-open
- New default open source driver for nVidia hardware
- Improved support for nVidia proprietary graphics drivers
- Social from the Start
- New boot experience
- New Indicators
- New Themes
- Ubuntu One File Syncing
- New features for Ubuntu Enterprise Cloud (UEC)
update-manager -din terminal and the rest will done by itself. You don't need to do anything. Just seat back in chair and take rest with a mug of coffee. Ubuntu updater will upgrade itself by default updater.
Official announcement here. Read the detail changes overview here.