The road map slide also hinted at new accessories and new colors for the Microsoft Surface line. In addition, during a Reddit AMA in June, a Microsoft team suggested that we could see covers for the tablet that will recharge the phone. There was also some discussion of peripherals to be available in the future, that would click into the tablet to work.
Last month, a published report noted that Microsoft is planning on updating the Surface RT by using Qualcomm Snapdragon chips. There is also some speculation that Microsoft has tested the zippy Qualcomm Snapdragon 800 on Microsoft Surface slates running Windows 8.1. Since that chip supports 4G/LTE connectivity, we could see Microsoft Surface tablets offer support for LTE with the next iteration of the slates.
source: WPC, TheVerge via Pocketlint