That's what I was thinking but I was afraid to liken it to them lol. It's honestly not all that bad stylistically - like the illustrative aspect is similar with back-lighting and all, but I think maybe compositionally it's lacking the cohesiveness and shape of Struzan's posters, and the colors are a bit too 'textbook'. I like the gradient from cool to warm, but it needs more complexity.
My main judgments are how Hagrid's flying from the castle instead of the abbey, and that the bike is shooting off sparks and not flames. Oh, and the composition of the logo at the bottom is odd. Overall I think this feels more like an approved concept than an actual finished illustration.
Anyways, we should both try and come up with illustrations!