He was found by his wife this morning and pronounced dead at 7:45 a.m. He was only 50! The cause of death unknown but he was hit on the head during a “rough landing” yesterday, the tire blew out on the plane:

There were no signs of a break-in, and investigators do not suspect foul play, said Lt. Brian Dugan of the Tampa Police Department, who would not answer any more questions about how Mays’ body was found because of the ongoing investigation. The coroner’s office expects to have an autopsy done by Monday afternoon.
[…]
“All of a sudden as we hit you know it was just the hardest hit, all the things from the ceiling started dropping,” MyFox Tampa Bay quoted him as saying. “It hit me on the head, but I got a hard head.”

Maybe he had a brain bleed like Natasha Richardson.
Update: His last tweet referred to his flight:

Just had a close call landing in Tampa. The tires blew out upon landing. Stuck in the plane on the runway. You can always count on US Air.

Another Update: His son’s tweet::

My dad didn’t wake up this morning.. I’m sure you’ll all hear about it. It hasn’t yet hit me but it’s about to.

TMZ has the video of the Billy Mays interview after the plane landed.