Adobe also announced today the availability of Adobe AIR 1.5, a key component of the Adobe Flash Platform, which enables Web developers to deliver rich Internet applications outside the browser. Offering new features and performance improvements to create more expressive AIR applications, Adobe AIR 1.5 incorporates the open source WebKit HTML engine and now accelerates application performance with “SquirrelFish,” the new WebKit JavaScript interpreter. Adobe AIR 1.5 also includes a new, encrypted database that meets enterprise security compliance requirements while storing data securely on customers’ computers. Additionally, AIR 1.5 includes functionality introduced in Adobe Flash Player 10, such as support for custom filters and effects, native 3D transformation and animation, and extensible rich text layout.

Adobe AIR 1.5 developer release notes
Adobe AIR 1.5 user release notes

Download Adobe AIR version 1.5

UPDATE:

A more detailed  explanation by Robert Christensen in the Adobe AIR Team Blog on  the post Introducing Adobe AIR 1.5

The Adobe AIR 1.5 by David Gamez, unless otherwise expressly stated, is licensed under a Creative Commons Attribution-Noncommercial 2.5 Mexico License.