We can come up with a couple of theories based on @evleaks' enigmatic message. First of all, @evleaks once again reminds us that he might have better inside information than all of us, as we've hardly heard anything "mind-blowing" about Microsoft's plans recently.
Secondly, and we're venturing into the realm of speculations here, Microsoft is attending MWC 2016 - call it wishful thinking at best, but we feel if any light will be ever shed on said Windows-related "mind-blowing" fact, it might happen during Redmond's endeavors at MWC 2016.
No, we're not expecting a new Windows 10 flagship smartphone, as the Lumia 950/950 XL got launched not that long ago, and @evleaks' tweet doesn't exactly sound like a regular device leak. On the contrary, we feel like something way more interesting is going on behind the scenes, and we certainly can't wait for more info on the matter...
Still, if Evan Blass knows something about that Surface Phone, we'd love to listen!