Fortunately, someone at Mojang heard the numerous questions and has an answer. Windows 10 edition and Pocket Edition are the same.

Windows Phone, or rather, Windows 10 Mobile (as will be the case here), fans have been causing a bit of a stir this weekend ever since Mojang announced an all-new Windows 10 Edition of Minecraft. The beta will launch in the Windows Store on July 29, but the biggest question has been what it will mean for phones.

Tommaso Checchi works on the Pocket Edition at Mojang:

"I'm going to say this because the drama is already too much: Windows 10 Edition is MCPE, and will always be updated together with it!" "That means that MCPE is going to get a lot of features, and that Win10 and MCPE players will be able to play together :)"

So, worry ye not. If you already have Minecraft: Pocket Edition, it's going to get a whole lot more awesome after July 29. If you want to play on Windows 10 PC you'll still need to download Windows 10 Edition, either for free or $10 depending on whether you currently play or not.

Those guys and gals at Mojang are alright.

Update: Since it still seems to be confusing some folks, being the same doesn't mean they're a Universal App for Windows 10. PC players will need to get Windows 10 Edition either by free upgrade if they currently play Minecraft on PC or buy it for $10 if they're new. The above tweets confirm that Pocket Edition players will get updates to bring it in line with the Windows 10 Edition thus creating the same game on mobile. It will still be a separate purchase as is indicated at this time. Minecraft: Pocket Edition is also available on Android and iOS and it's safe to assume these versions will also become on par with the Windows 10 Edition.

via WindowsPhoneApps.es