From the article linked above: "According to reports, Binder said Carradine's hands had been tied behind his back and a footprint on the bed did not match his shoes."
I'm not a law enforcement professional, and I didn't sleep at a Holiday Inn Express last night, but if the dude's hands were tied behind his back, wouldn't that tend to push suicide down the list of potential explanations for his death? Of course, I guess you can't really rule out anything if the guy was playing rodeo cowboy with his Johnson. Tough way to come out of the closet....