Required for Flash video streaming:

• download the .tar.gz file
• decompress it to extract its content:

  tar xfv install_flash_player*.tar.gz
• replace any existing file at /usr/lib/mozilla/plugins/libflashplayer.so
• re-start the Web browser

Dependencies: +bzip2,+cairo,+fontconfig,+freetype,+glib,+libnspr4,+libnss3,+libnssutil3,+pango,+pcre,+pixman,+libplc4,+libplds4,+libsmime3,+libssl3

N.B. Adobe Flash Player 11.2 will be the last version to target Linux as a supported platform. Adobe will continue to provide security backports to Flash Player 11.2 for Linux.

Verify installed version (requires javascript enabled)

For full functionality ensure that the Web browser's JavaScript setting is enabled:

• SeaMonkey: Edit > Preferences > Advanced > Scripts & Plug-ins > Enable JavaScript for Browser
• Opera: Tools > Preferences > Advanced > Content > Enable JavaScript
• Firefox: Edit > Preferences > Content > Enable JavaScript

FlashExtractor - view and manipulate Flash files
Gnash - Alternative Flash Player

http://lwn.net/Articles/346389/
http://secunia.com/advisories/search/?search=Adobe+Flash+Player
http://www.phoronix.com/scan.php?page=news_item&px=MTA2MDc
http://www.zdnet.com/blog/open-source/adobe-abandons-linux/10418