Oh I agree, it shouldn't be advertised as a headline feature if it's not fully functional. I'm just pointing out that Microsoft considers Cortana to be in beta, and it's only available on the developer preview of the OS. With that in mind, it's possible that Cortana just isn't doing everything that it should be doing, and thereby isn't quite as useful as it could be.
As someone who uses Siri all the time, I can't wait unt Apple copies 3rd party app integration. There are a number of very small tasks I do repeatedly during any given week that Siri could easily take care of if integration points were available.
