The Opera Desktop Team announced Thursday the release of Opera 10.5 beta for Mac. The new release includes the return of Tiger support, a Cocoa build, support for Growl notifications, support for multitouch gestures, as well as a multitouch gesture easter egg that no one seems to have yet found.
The release also ends support for PowerPC, and the company said that some users may experience performance issued in Mac OS X 10.4. There is also "minimal" support for Java in the build.
You can get more details if you want to parse through the changelog. The browser is available for download at the company's site.

Bryan Chaffin
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Three-finger swiping up & down move a screen at a time instead of scrolling smoothly. Could that be the Easter egg?