Being Google, there are some really cool commands in there like "do I need a jacket today?" and "turn on wifi".
Having suffered a neck injury a couple years ago, it affected one of my hands and made it hurt to text. Now it's easy to text someone by saying "OK Google text this person" and then you dictate the message with your voice, confirming at the end to send. This feature is still a little more basic than it should be, but already incredibly useful to someone like me who won't drink the Apple koolaid no matter how much it hurts to type.
Another of my favorite new voice commands is "OK Google set alarm for 9 AM"
Here is a really good writeup of the new commands as well. All you have to do is say "OK Google" to active a voice command. One of the commenters claimed that you can say "Ok dude" but that doesn't work for me.
Some of my useful favorites:
"What's the weather?"
"What time is it in [place]?"
"Navigate me to [place]"
"Send a text to [person]"
"Wake me up at [time]"
"Do I need a jacket?"
"What is the next turn?"
"What time will I get there?"
"Go go gadget [app]"
"Do I need an umbrella?"
"Read the last text"
"Are we there yet?"
"How far is [place]?"
Some of my fun favorite "easter eggs":
"Beam me up, Scotty"
"What does the fox say?"
"Who's on first?"
"Make me a sandwich"
"What is the airspeed velocity of an unladen Swallow?"
"What is the loneliest number?"
"Hello. My name is Inigo Montoya. You killed my father. Prepare to die."
Some of my interesting favorites:
"Flip a coin"
"How old is [person]?"
"Who is [person] married to?"
"Who wrote [book]?"
"When is [holiday]?"
"When is the next episode of [tv show]?"
"What is the tip for [amount]?"
"What is the word for [word] in [language]?"
"Is John Snow dead?"