Next fall before Halo releases makes sense. There will not be a Kinect-less SKU. Sony is losing money on every PS4 sold so I don't expect them to react for while anyways. Especially if the PS4 is selling well they wouldn't have a reason to drop the price. If both consoles are selling well then I expect a Xbox One price drop in 2015. Its simple economics.

Since launch has come close and no news, i bet they will do it on E3 2014.
But lets not forget this:
http://www.mcvuk.com/news/read/microsoft-selling-xbox-one-hardware-at-a-profit/0120691

I would think this depend on what they sell, probably near the holydays 2014

This time next year they will drop it $50. They will mix in some add in games to the system. That and their subscription programs for XBlive.

Not before a year. Pre-orders are going very well and I do not see why they would drop the price already...

Golfgt170 got a very good point too, they are already selling at profit, so if they can manage to get a year with that and then drop the price it would be the best strategy.

Before MS will consider a price drop they'll likely heavily bundle it with some games before consider dropping the price.

I'd say less than a year. they're probably not taking a loss this time, so an early price cut is possible, especially when the chances are high that it will have a slow start.

Kinectless?

I think it's more likely a Disc Driveless Xbox One to hit the market in 2 or 3 years.

lol, a kinect-less sku would never break even at those prices. it could be 349-399.

No way. The launch consoles will sell out. The money they gain from them may as well be on the bank. Why would you take it out? They're better of waiting.