Read about it all here:
http://www.solidsmack.com/bunkspeed-get ... 010-01-08/
"Hypershot is no longer. Luxion, developers of the render engine behind Hypershot, has pulled it’s render engine from Bunkspeed who are now using Mental images’ iRay solution. Both Luxion (Keyshot) and Bunkspeed (Shot, I believe) are going to provide software to fill the gap left by Hypershot."
So now, instead of Hypershot, which was easy to use and used Luxion's rendering engine, Bunkspeed has "SHOT". "SHOT" uses Mental Images iRay rendering technology.
Luxion, basically made their version of hypershot, with different icons, and it uses the old hypershot rendering engine.
Which is better? Who knows. I'm currently using Hypershot 1.9, and it works great. It'll be interesting to see two almost identical products compete, but I'm a bit sad since I've been a hypershot user/fanboi since it's inception.