LG Nexus 4's Internal Storage Dilemma & its Apparent Lack of Support for USB OTG Connectivity?
USB OTG compatibility is more dependent on the kernel than the actual operating system.

If the stock kernel doesn't support it, then it will (most likely) only be a matter of time until a custom kernel is released that has this functionality.

If you were to purchase it, remember that the tablet can only give 5V of power to the device - this stops you from using things such as portable hard drives with the device, which require a large power input.

You would be best asking on a dedicated ROM'ing forum such as XDA-Developers to find out if the stock kernel supports USB OTG, and if not, a custom kernel can be made to support it.

Please be aware, that you will need an app that allows you to use the USB OTG support.