Wait, what? my understanding is that all Sony Google TV hardware is still on Honeycomb 3.2 O.S and they have no intent to upgrade to Jellybean 4.2.2 anytime soon. Are you saying your Sony NSX model has received an O.S upgrade? Basically, Jellybean on Google TV removed flash support which is what happened when LG updated their Google TV's to the latest Android O.S. If you are currently running 3.2, yes the slingplayer was removed from spotlight but can be still accessed through a chrome bookmark link
MY Sony GS7 and GS8 Google TV boxes still function with the slingplayer weblink.