Schmosby hit the nail in all of his points.
This isn't a press event or even a press release by any means. Rather, think of this announcement as a hesitant confirmation. The news had broke to a point where it became widespread knowledge. Universal, at this point, had to confirm something.
As for the EP, I doubt there would be an event for that. Remember, the EP is more like a basis for what could happen in the next 5-10 years - not a confirmed, master plan to the extent that California Adventure is/was.