I haven't had time to check the updated beta out but here are a few highlights from the A9 "What's New" page.
+ More Intuitive Search Column Selection: The buttons on the right have been replaced with checkboxes on the top. These checkboxes let you choose what to search. The checkboxes appear not only on the search results page, but also on the home page, so you can decide in advance what to search.
+ Faster Site: The home page is now much smaller and loads faster, especially if your personalized tools are turned off.
+ Easier Access to Additional Search Columns: In addition to checkboxes for the default set of searches, a "More Choices" dropdown provides easy access to additional searches. (The contents of this menu will change over time.) You can also use the menu to access over 100 additional OpenSearch columns.
+ Opera 8.0 support: Columns can be resized in Opera 8.0.
FYI, the features described as "new" in a Seattle Times this article have been a part of A9 since it went live last year.