I just saw it a few hours ago and first had to calm down after seeing it before writing something here. All in all: I absolutely loved it!!! I can really just tell you that you should go and see it and I really just want to see the next part now, and not in 2 years...
Johnny was greeeeeat it is a fabulous role for him and he perfectly fits in this universe. He is surely evil, cruel, manipulative...but still fascinating and seductive, I looooove it! His acting is calm, not over the top, you don't see much of his style which you can see in many other movies (not saying that he is doing the same over and over....but this role is really extraordinary different!)
Johnny aside, now to the general movie.
Maybe first the negative things: I can see that one can argue that this movie hasn't moved the bigger plot that it supposed to go through all five movies forward a lot, but neither has the first one I would say and still I enjoy both movies. But one has to admit that somehow there is not really that much new stuff concering this, that you learn during the movie, but for me it is okay because it is still important stuff that is going on and important decisions are made, and of course there are revelations made!
Sadly, one of them for me as a potterhead is somehow really difficult, though, and the other one I'm not so sure what to think about:
► Show Spoiler
Credence being a Dumbledore, I mean...how? A sibling of Albus he and Aberforth and everybody in the Potter books just happened to forget about? Or is he not a direct brother but rather a...nephew, cousin, I don't know...?! I don't like this idea at all...
My personal favorite explaination would be that Grindelwald is lying about it, just to make Credence fight Dumbledore, but I don't feel that this might be a good explaination, because of the phoenix and... well why all the Lestrange backstory plot and the whole film about Credence wanting to know who he is and then just telling a lie?!
And the blood pact part: Well somehow it is good to know that Dumbledore did not just have problems moving agains Grindelwald now, because of some juvenile love/fascination, but that ther is a hard, magical reason he really CANNOT move agains him, on the other hand its also sad that now it feels like the emotions don't play that much of a role anymore...
Also difficult for me is the appearance of a character of the potter books:
► Show Spoiler
McGonagal, she is not as old as Dumbledore... But I think at least it is never stated in the books how old she is, but just in some J.K. Rowling background information so I can somehow live with this one, although then I really hope that she gains more importance in the following movies because up to now her appearance just doesn't fell necessary and I don't like that
But now after this criticism back to the good stuff (at least my favorites, besides Johnny because I mentioned this at the beginning):
I just can repeat what Ade wrote: I mean what's going on with the people complaining that it is too compilcated or complex? I don't see it and my mother who is not a big potter head also had no problems following it...For me it is just the right amount of story for the length of film.
There are beasts in it again, they are really cute and funny, some a little bit scary, and I like how one of my favorite beasts does something so important towards the end of the movie.
The story is well thought, I like how the charactes have all their decisions to make and how the audience gets to see it and, somehow, also like Ade wrote, can understand each single one no matter whose side they pick!
The soundtrack is great again, the whole movie is way darker than the first one but it fits the story and setting, the special effects and the use of magic are great, and it just all makes me so curious on how everything will evolve from there....
I think I could go on writing about it forever, but I will stop now, and maybe add something in the discussion, once some of you have also seen it and written down their thoughts. I'm also really curious what you think about the thing I kind of criticised in the spoilers....