There has been disputes between fans whether the Edward Norton edition of “The Incredible Hulk” is really a part of the MCU – and a few fans claims that Iron Man was the first one and the Hulk movie was not counted as a MCU release. One argument is that since Edward Norton made the first version and therefore is not counted as an MCU movie, even if there are actually post credit scenes present that states the difference.
This is also important to keep our MCU timeline up straight and furthermore correct.
In an interview with Rotten Tomates, it is confirmed that The Incredible Hulk was a part of the MCU and the second movie, even if the watch order (chronologically) is different to the timeline. Hear Kevin Feige himself in the special video below.
The full interview about Phase one can be seen below.