In the following video, Motley Fool tech and telecom analyst Andrew Tonner tells investors what has shares of BlackBerry (BB 0.70%) up more than 10% today. AT&T has announced that it will be selling BlackBerry's Z10 handset as soon as March 22, while Verizon says it will also be selling the handset before the end of March. Is this the continuation of a successful turnaround story? Andrew tells us that while this is definitely good news, the company still has a long, hard road ahead.