Nope. Sleep/Wake sleeps the system, but when you turn it back on, you're restored to the app from before the last sleep. If that app had locked up, you'd still be stuck there. Sleep/Wake doesn't ever return you to the Springboard, so we need a hardware way to get back there.
Granted, but do you have any idea why do Android evangelists troll an Apple site?
They don't have any forums of their own. Seriously, there are Android forums, but they're exclusively help forums. I've yet to find a website for Android (or ANY of the individual companies that make Android devices) that carries the same tone as AppleInsider, et. al.
I don't get it either. Why don't they call it Samsung-Voice then?
The name is a direct ape, no question about that. Did you notice that the microphone is… well, isn't it the exact same type of microphone used somewhere in iOS?