I've been looking at quite a few good desktop applications built on Adobe AIR (such as eBay Desktop and Twhirl), and am pleased to report that ReadAir, a spin-off of Google Reader that was released on Thursday and is coded to run on Adobe's cross-platform solution, ranks among them.
ReadAir mirrors Google Reader's functionality with a cleaner interface and the deliberate adoption of the Mac OS X look. The left sidebar sorts items by the total harvest, starred favorites, and shared stories, with your tags directly below. In the top-right pane, elements such as story titles, sources, and dates are displayed. The selected story fills the lower panel, with gleaming blue scroll bars to guide you to the conclusion.
Readers can interact with content much the same way that they can online. A plus sign in the bottom left allows for adding and removing feeds and tags, and a search bar up top lets you skip the scrolling to find articles of interest by keyword. There are also links at the story's end for permalinking, e-mailing, and leaving comments that transport you to the source URL. Trend analysis is absent on ReadAir, but so far that's not preoccupying early users as much as the reader's inability to minimize the window to the task tray. Note that the app is in early alpha and will change often, making it a good idea for users to enable autoupdates.