Cortana Coming to Windows: Bigger Than Anticipated?

In a recent interview done by the BBC with Microsoft research's Eric Horvitz, a unique conversation of artificial intelligence unfolds. Towards the end, he says something somewhat intriguing. Listen for yourself.

When asked if he could talk about anything relating to cortana coming to windows phone, he replies by saying,

"Well i'll just say that personal assistance, mobile and across devices, is a very very important direction for microsoft and microsoft research." - Eric Horvitz

Do you think that cortana's ambitions may be bigger than we realize? And could it possibly simply be beginning with windows phone, while later expanding to every microsoft product? Only time will tell. In the meantime, I sit here anticipating what april holds.