Just so people are aware, the Rift is supported in SteamVR. Valve doesn't discriminate. All they want to do is sell software. It's a common misconception that only the Vive will support steam. The only exception is a handful of games designed for the motion controllers, but at this stage they are mostly glorified tech demos (not necessarily bad, just temper your expectations). It will be a while before developers have a larger budget (and the time) to make games that fully take advantage of those controllers since they're so new. Oculus' motion controllers (Touch) are an optional purchase coming out in the second half of the year. Total price of Rift + Touch will probably be the same as Vive.
Hard to go wrong with either device, but from an ergonomics standpoint the Rift looks superior, and it also has a high quality integrated audio solution (Vive ships with some throwaway earbuds). Supposedly it's just like putting on a baseball cap with almost no weight (it's even covered in a fabric so it can breathe).
I am not 100% decided on which one though... I did get a rift order in for the early shipments, but I can cancel that if I go Vive. They don't charge til it ships. I figure if it doesn't work out I make a profit on eBay anyway.