I'm pretty sure it's the latter. Microsoft's MO lately has been to rip off anything that makes their primary competitors unique, so they can go on being a one-stop shop in any industry they believe themselves to be a part of. And since Google is both a big competitor and lacking any central concept to its business, Microsoft will pretty much rip off anything they do.
yet, microsoft has deployed voice recognition to some hundred millions users over time, so they could have copied that idea to improve something they were already selling.
