Ground Branch is in the tradition of the original RB6 titles.It has good potential in the fact you can choose which game modes and number of players you want from server side which makes it more clan friendly,there also will be mod support for additional map's similar to CS.
I've been following it's progress over the years and it's now really starting to take shape.Put it this way it's worth keeping an eye on ;)

https://www.youtube.com/watch?time_continue=55&v=0m5Sq5n257k

Great news,Ubi have stated they have a 5-10 year roadmap for rainbow 6 )

http://www.pcgamer.com/ubisoft-to-stop-selling-compulsory-dlc/

http://rainbow6.ubi.com/siege/en-US/news/detail.aspx?c=tcm:152-259773-16&ct=tcm:148-76770-32

http://forums.ubi.com/showthread.php/1387463-In-Depth-Patch-Notes-%96-Update-2-1-%96-February-11th-(PC)-amp-February-16th-(Console)

Rainbow Six® Siege PC free this weekend

If you already own the game just click the link and get your 4 codes to give to your friends,n1 Ubi;)

Running from saturday, December 19th at 12:01 AM CET and ends, December 21st



https://rainbow6keys.ubi.com/en-GB