What’s New in 10.04
The 10.04 Lucid Lynx release of Ubuntu sees a switch from the Humanity theme that has been used for many years to one based on Light. The first impressions of Ubuntu forum users was that the new look is “sharp” and “impressive.” I think so, too. But you will need to get used to a few things such as the minimize, maximize, and close buttons being at the top left of each window (rather than the top right), as shown in Figures 4-49 and 4-50 (which reveal two versions of the new themes, Ambiance and Radiance).

Figure 4-49. The brand new Ubuntu Ambiance theme used in Ubuntu 10.04

Figure 4-50. All themes are configurable and this is a lighter version of Ambiance called Radiance
Although the Ubuntu forum users loved the new styling, only about 8% were in favor of the buttons being moved (as of this writing, that is). Therefore, by the time the final version of 10.04 is released, it is possible that some things may have changed again. If you find the new styling too different for your tastes, you can easily change it by selecting System → Preferences → Appearance and then either choosing a new theme (perhaps, the old Human theme), or you can click the Customize button and refine a theme to your preferences.
You can also press Alt-F2 and enter the command gconf-editor
gconf-editor ...