Seems like Notch just wants us to make an entire game for him this time.
Won't be surprised if it's comprised of over 75% fan ideas and creations. Minecraft's "full" version already has way too many mods...not to mention unfinished graphics. Makes for a really disjointed and non-cohesive piece of software.
And a monthly fee? Does this fat manbaby millionaire really need to pad his already bursting wallet any further?
Cool story. Feel free to not buy it. Alternatively, feel free to buy only single player. --- Currently awaiting: Pikmin 3, Lunar Knights 2, KH 3D, Pokemon BW 2, The Last Story Skarmory would slap the hell outta you