I've never seen how this is an MMO, I think it's just called that to hype up this idea of it being a free MMO when it's not. Did everyone go WOW! YOU CAN PLAY DIABLO WITHOUT A SUBSCRIPTION! ITS SO MUCH BETTER!! No, why is everyone suckered by this? It's going to end up being an even more shallow version of Diablo, that you have to upgrade every couple months to remain competitive in PVP.
They've said they don't want people to need to grind to get items to win PVP, so the reality there is instead of having to quest for your items for PVP you'll need to buy the upgrades to PVP, otherwise nobody in their right mind would ever buy an expansion and they'll figure that out if they don't know it already.
The PVP is pretty fun, but if they stick to their words about not having an advantage from getting loot in PVE then whats the point of even having it? It's not really fun, the only reason anyone does it is for items. If the items don't mean anything who cares?
Or maybe they are lying about not wanting people with more time to have the advantage, I guess it might be too early to tell. But having 3D lobby rooms does not make it an MMO, when you have to tell your friends meet me in Room 132 instead of meet me in Stormwind...