According to the folks at Windows Phone Central, they have heard that Microsoft is currently in the process of recalling Surface Pro 2 units and related accessories back to Microsoft. It is unclear why Microsoft is doing it, but they speculate it could be that Microsoft making way for a new Nokia Lumia tablet.
There is currently no evidence that Nokia could have a new tablet up their sleeves, so this is purely speculation for now. Alternatively it would make sense for Microsoft to recall the Surface Pro 2, especially with the release of the Surface Pro 3. They also point out that the Surface Pro 2’s listing on Microsoft’s website has not been bolded, unlike the Surface 2 and the Surface Pro 3, suggesting that Microsoft does not really want to draw attention to the tablet, instead focusing on its successor.
In the meantime if you still had your eye on the Surface Pro 2 because it is a cheaper alternative to the Surface Pro 3, you will still be able to order it via Microsoft’s Surface website.