Lumia 2520 and Surface 2
"Microsoft has released the Surface 2 and Surface Pro 2 ... Fourth-quarter sales figures will be interesting to compare come January."
Indeed, the 2520 isn't exactly the same as the Surface 2-- but they're pretty close, and the differences will become smaller once Microsoft ships the LTE version of the Surface 2 next year. The Lumia is cheaper than the Surface 2 if you're willing to eat the contract, but with the Nokia acquisition closing, Microsoft will have to balance two very similar devices, both of which are pitched at what has so far been a niche market.
Microsoft already faces strange competition in that its Surfaces compete with Windows devices from HP, Dell and other partner OEMs. But with the Lumia 2520, Microsoft is primed to face competition from itself-- which is stranger still. Then again, Microsoft might not care about Surface 2 sales if the total Surface 2-Lumia 2520 install base grows large enough to make Windows RT a viable platform. Hardware profits in the short term are a small concern compared to the longterm viability of the Modern UI.