Back in October of last year is when Flash Player 11.2 went into beta across all supported platforms. Unfortunately, in February is when we received news that Adobe would be abandoning Flash Player Linux support.
Going forward, Adobe will just be maintaining Flash 11.2 for Linux and not be providing any new releases. Flash 11.2 will be maintained with security/bug-fixes for a period of five years. Meanwhile, Adobe is letting Google work on Flash support inside their Chrome/Chromium web-browser using the Pepper API (PPAPI), but this interface isn't supported by Mozilla Firefox or other web-browsers. Flash Player for Linux will no longer be available as an independent x86/x86_64 library.
Linux desktop users are left to either using Flash Player 11.2 indefinitely, use Google's web-browser on Linux, or to ultimately switch to one of the open-source alternatives like Lightspark or Gnash. Sadly, these open-source Flash/SWF alternatives are hopelessly outdated and don't always work well -- even for YouTube and other popular Internet destinations. Linux users can just hope that within the next five years that Adobe Flash becomes dead and replaced by HTML5 and friends.
As far as the Flash Plauer 11.2 Linux changes, there's improved driver compatibility for video hardware acceleration (though it's still NVIDIA VDPAU and Broadcom CrystalHD limited with no VA-API / XvBA support), a new throttling event, event improvements, and multi-threaded video decoding support. The 11.2 update isn't anything to get too excited over unless you're a NVIDIA GeForce/Quadro owner and use the VDPAU-supported proprietary graphics driver.
Those interested in grabbing this week's Flash 11.2 Linux update can find it in this Adobe Forums post.