Some of the highlights in 12.04 for my money are:
- Boot time - the whole process seems faster to me, which is an achievement given how much more is going on under the hood.
- Performance. I can add the whole release is running much more smoothly than 11.10 and certain operations run noticeably faster.
- Previously, the Unity Files lens would only find files you've opened (based on the Zeitgeist activity logs). In 12.04, the File Lens can also display results for all files in scope, even those never accessed.
- Unity (2D and 3D) has an option to configure the launcher for multi-monitor setups: you can now select to display the launcher on the primary monitor or on all monitors. The Launcher behaviour for multi-monitor setups can be also set from System Settings (Displays, under Launcher Placement), where you can now also enable/disable Sticky Edges.
- The HUD improvements include a new animation and respect for the launcher behaviour (autohide, visible) and launcher icon size
- The HUD, or Heads Up Display is a smart menu for search that can be summoned by tapping the ALT key.
- Ubuntu 12.04's Unity launcher now comes with quicklists for most default applications. For example Rhythmbox, Empathy, Remmina, Totem, Brasero and Gedit have active quicklists. Righ-click the icon in the launcher to find out what operations you can access.
- Ubuntu Software Center now has a Unity launcher progress bar support. The icon is automatically added to the Unity Launcher and a progress bar lets you know the installation status.
- The Ambiance and Radiance themes are updated with new titlebar gradient, unfocused state, darker Nautilus sidebar and numerous tweaks
- Unity 2D finally looks like a true twin of Unity 3D. The Launcher, Dash and the Unity panel now use the same look as Unity 3D
- Unity 2D also got HUD support
- Ubuntu 12.04 has the latest GNOME Shell 3.4 in the official repositories, along with most other GNOME 3.4 applications and components.
If you haven't already, take the 12.04 upgrade, it is a worthwhile update for a whole raft of incremental improvements.
You can either download Ubuntu 12.04 LTS Precise Pangolin as an iso image, or take the in-place upgrade.
To upgrade to Ubuntu 12.04 from 11.10 or 10.04, press ALT+F2 and enter: "update-manager -d" (without the quotes), then the Update Manager should display a message saying that a new Ubuntu version is available - click the upgrade button and follow the instructions. RC