No, Jon Jones has not been cut by UFC. Repeat: JON JONES HAS NOT BEEN CUT BY UFC. But it was an apparent (and funny) typo on Brandon Vera's Twitter that was quickly removed yesterday:
"just found out I’m firing Jon Bones Jones on March 21st in Denver Colorado. hope u heard it here first!!!!"
From Cage Potato:
We can only assume that Vera meant "fighting Jon Bones Jones," and that he won't be flying out to Denver to terminate Jones from his contract, Clooney-style. And the March 21st date may also be a misprint: MMA Junkie and MMA Weekly both report that the yet-unsigned fight is actually slated for March 31st, and will headline an Ultimate Fight Night card just four days after UFC 111 (March 27, Newark). The 3/31 Fight Night show will lead directly into the premiere of TUF 11.
Unless Vera has somehow taken over Dana or Donald Trump, I don't think he's "firing" Jones even if he wins. Still funny though.
Edit: Slightly changed the title so people don't get the wrong impression.