This does NOT sound good.
With the help of this site (and easywdw), I had our November trip planned to the most minute detail; however, the word of the trip was "fluid". I kept saying to my SIL and nieces, "Check your calendar, this is our itinerary for the day, but our plans are fluid. We are not married to the schedule".
When we were able to score dinner ressies at BOG, we snatched them up, and bailed on our DHS afternoon/evening and changed the whole day to an MK day. As a result, we later needed to change a flex Epcot day to a DHS day.
FP+ will take away that flexibility. Score a BOG ressie, kiss off a TSMM fastpass plus. Doesn't sound like a fair trade to me. I am starting to think that the die-hards on this site might be right. I need to check underneath all the sofa cushions and see if I can find the extra thousand or so required for the flights to California ... or share the wealth with Universal, for a change.
I know it's early days and things may yet change, but I think the pixie dust I have admittedly been sniffing, is beginning to wear off.