If that's what I think it is, it's either the hoax image of the Spy update that was filled with grammatical errors, had a phony 'Meet the Medic' picture (in-game, not HD from video), and said the weapons were a Tranquilizer Gun, Garret(?), and an unremovable sapper that did no damage and lasted a long time. Two of those weren't feasable IMO. That or you mean that YouTube video someone posted? It was a Rick Roll then at the end had a phony "Tranquilizer Gun Unlocked!" screen at the end.
Well at any rate, the day the Heavy update is released, there will be 8 heavies on each team with the rest being filled by Spies/Snipers killing those heavies. I'm no good with Heavies so I have no idea what they'll get. Probably won't be something that boosts speed or a shield though. Valve stated they wanted to make Heavies less Medic reliant but not more potent with them. So any unlocks they get will have to have some unattractive factor that won't be the prime Medic buddy choice.
Uhh, no, I just typed into google "heavy update TF2" then copy and pasted the text from the first box
. Hope that clears things up for you.
















and theres plenty of demonstration videos of it on youtube as well as other metal storm designed weapons.