Via BlackBerry Dev blog, AIR 2.7 update is available for BB Tablet OS.
“The next generation of Adobe® AIR® on the BlackBerry® PlayBook™ tablet has arrived! With the availability of a new Adobe® AIR® 2.7 runtime, developers will have full support for Adobe® Flex and Adobe® ActionScript on the BlackBerry PlayBook tablet. The new Adobe AIR runtime is now available for free to BlackBerry PlayBook tablet owners, who can download it over Wi-Fi® using the “Check for Updates” option on the device.”
Check the dev forum for more details.