Developers have been releasing "Gutsy Gibbon" builds since May, but the "Tribe 5" alpha release this week previews many of the significant features planned for the final release when it appears in late October.
A top Ubuntu design goal is ease of use, and several of the additions are user interface and configuration tweaks. A new graphical interface has been added for making adjustments to monitor settings, for example.
The interface is intended to make it easier to choose graphics card drivers, set up dual monitors, change the default resolution for all users or change the monitor's refresh rate, settings for which users might previously have had to resort to the command line. Ubuntu's version of Firefox has been updated with a new plug-in finder wizard, as well as with an integrated extensions manager, developers said.
Printing also has had an overhaul, with a virtual "PDF printer" set up by default to allow any application to output into PDF format. The old printer management system has been replaced and a new configuration tool should mean that printers are set up just by plugging them in and turning them on, developers said. The Tribe 5 release also includes the latest version of the Gnome desktop, the public test version of what will become Gnome 2.20.
Other additions scheduled for the final release include faster desktop search, fast user switching, a new deskbar applet and the AppArmor security framework, released as open-source software by Novell. The final release is scheduled for October 18.
Gutsy Gibbon's successor, Ubuntu 8.04, scheduled for release in April 2008, will be the next version of Ubuntu to receive long-term support.
Canonical, Ubuntu's commercial sponsor, has said it plans to release long-term support versions every two years. The current final version of Ubuntu,, brought in a migration assistant, KVM virtualization, a simplified mechanism for installing codecs and restricted drivers and other features.
Earlier this month, Canonicalover Ubuntu after several servers set up to help promote localized versions of the operating system were compromised and used to attack other servers.
Matt Broersma of ZDNet UK reported from London.