So who is NOT getting Heavensward?!

[Reinha]

Let me reverse that question by asking you which MMO's you've played which have?

World of Warcraft. The level cap raise is mentioned in the list of things you get with the expansion.

Edit. Basically ARR is now over and no new content is going to be added to it, if it follows WoW's model. Patches will be for people who bought Heavensward even if stuff is located in the old world. Personally I think 2 years worth of content is pretty good for any game and well worth the money.