Here’s a simple summary for anyone with issues with their Surface Pro 2, and what information is floating around. Compiling this after having to read at least four dozen pages of forum posts, and a trip to the Microsoft store.

Symptom: You installed an update in December (or Windows did for you), and ever since then, your Surface Pro 2 has been waking itself up from sleep and hibernation.

Reason: Probably some issue with some USB-related driver, based on what the Event Logs show. The underlying issue is a bad firmware update that has since been pulled by MS.

Fixes:

1) Wait until January 14th, the day an MS store employee told me the fixed firmware would be released. I take it with a grain of salt, but it is a Patch Tuesday, so that sounds about right. There’s probably a memo trickling down to customer support.

2) Install the “System Hardware Update” update that appears now, with a size of 204kb. This will allow you to boot into the UEFI of the machine (Vol Up when you power it on), and install the Default Secure Boot, which will reset the machine back to the October firmware, according to MS support. Then wait until the January firmware fix.

What helps: If you have a microSD in the machine, take it out. Evidently, a separate issue is causing the device to idle at very high CPU usage, especially during boot, which will kill the battery even faster during the sleep walk bug. Shutting down completely should avoid the problem. Disabling hibernation will prevent this, too. Disconnect any USB/display port devices when the machine is on hibernation, which will, at the very least, reduce power consumption.
Most of this info is extracted from this MS support thread, as well as other discussions with myself and other people. Best of luck to anyone who is affected, and this post will be updated with any new info.

Update: The January update seems to clear this up, but still leaves some other issues (i.e. SD card) stuck in place. Hoping for more updates soon.