This rumor comes up every year. There would be no advantage to them releasing an Android device. They wouldn't get any cut of app sales, they can't control Android security (which is an absolute joke), and people still won't buy it because it's a BB.
I'm a die hard BB fan. I've had 6 or 7 BB devices since 2004 (currently a Z10 running 10.3.1) and I'm a 10+ year BES admin. The BlackBerry 10 OS is solid, secure and fast. Give it time. A lot of time. It already runs most Android apps.
Android is a mess. It varies wildly between phone manufacturers and it is dominated by 2 or 3 companies. Don't go down that path.