A recently posted wiki page and a Chromium project page describe Aura as "a new accelerated user interface framework for Chrome UI" which "must offer rich visuals, large-scale animated transitions and effects that can be produced only with the assistance of hardware acceleration."
There isn't much detail and not even mockups beyond basic window buttons such as restore, maximize and minimize at this time, but the Chromium revision blog is, with more than 400 changes to Aura over the past two months, an indication that Google is working on a major new feature.
The new interface will mark a departure from the Gtk toolkit, which has been used for Chrome's interface so far and may take Chrome much closer to a platform that can compete with (and possibly go beyond) Windows in a cloud environment. Google said that its main goals for the initial release of Aura is cross-platform code for a "flexible windowing system" on multiple form factors. The company said that it will initially not support multiple monitors and there will not be software rendering support for remote desktop capability.