But at the same time, there are loads more details missing. The fake galleons for one that would tell the date & time of the next DA meeting. Also, Harry's birthday present from Sirius, the mirror that'll allow him to speak to Sirius. Another not-so-small detail is the fact that Petunia knows about the dementors. There is no mention of this in the movie. Personally, I find this movie an extreme disappointment after reading the book(s).