Oddly enough, they found Judge Crater in a crater.
A dead cat.
Curiosity did it, y’know.
A crater or cavern full of mismatched socks.
The discovery: A metallic disk that when played sounds something like, “Ack Ack, Ack Ack!”
Better upload some Slim Whitman onto Curiosity, just in case.
Darn it, DMARK stole my joke.
I am very excited to learn what they found though.
A Shadow ship.
Prothean ruins.
Comet Kohoutek.
Whatever it is, if it is something that is only of real interest to Mars buffs and space exploration nerds, can NASA kindly keep their “important announcements” to internet bulletin boards and stop giving our media reasons to gush even more bullshit than usual?
Never tell me the odds.
Overlaying a layer of car keys one presumes.
I expect something eye-rollingly boring, along the lines of what others have said. Maybe it moved a long way in a single day.
Every morning, I run to the computer and check the news for this Earth (heh) shattering discovery and, so far, nothing.
WTF IS IT!?!
I have a RIGHT to know! And NOW!
The article I’d say it was something based on soil data that they wanted to retest multiple times, to be sure.
So maybe something better than that! I hope!
Oil! 
A Chinese base.
Ding ding ding ding… we have a winner!
Wouldn’t it be fun to move to Mars and be encouraged to pollute the atmosphere with as many GHGs as possible? That’s a capitalist dream!