I called Springfield Armory, and indeed, I can confirm that it has been discontinued.
This is a FANTASTIC gun, and it's a shame it's gone.
If you'd like to see how the M6 does against a menacing beer can, have a look at this quicktime movie I made for someone who lives in a gun-limited place:
http://www.focazio.com/boom/BudBoomMed.mov Your next-best alternative for a survival rifle is the Savage Arms combo 12/Rifle, in a variety of calibers.
http://www.savagearms.com/24f12.htmI'm picking one up in 12 Guage/.223 or possiblt 12/.17 soon.