Now that PS4 and X1 are both going to be $399, which will now sell better?

[Salnax]

I imagine that the near future will follow this pattern:

• Until Price Drop - Xbone steadily loses sales as people wait for new sku, PS4 gains grounds in late May with Wolfenstein and Watch Dogs
• June to July - Xbone surges ahead especially in North America, where it dominates the 8th gen console market. People forget about the last year or so of bad Xbone press if Microsoft has a good enough E3 or if Sony has a bad one.
• Rest of Summer - The two consoles are neck and neck, thanks to a lack of major new 8th gen exclusives.
• Latter 2014 - Microsoft's big bucks and exclusives pay off, as North America buys a shit-load of Xbones in Q4. Games like Sunset Overdrive, Halo, Spark, etc out-rate and perform the PS4's exclusives like The Order: 1886. Meanwhile, the launch of the Xbone in Tier 2 countries and China gives at least a temporary boost. Thus, even though the PS4 dominates more of 2014, the two consoles end the year with similar amounts of hardware sold.
• 2015 and Beyond - Depends on a bunch of things, like the E3 in a month, whether the Wii U and non-gaming devices steal casual sales, how consoles are received in China, etc. However, neither console will ever gain more than, say, 60% of the market, with the two competitors at worst sharing the remaining 40%.

In short, hard to say either way. I'd say the Xbone might sell better lifetime due to: Japanese support, a PlayStation staple, declining and moving to handhelds; the Xbone's reach into China; having a better known online network; and stuff like Call of Duty exclusive content.