I went to watch DooM the movie on the weekend. Lotsa memories came flooding back. In particular, they missed a huge part of the movie.
(a) No monsters - sure they had these imp like things with eyes. They missed the cacodemons, lost souls, hell knights and most importantly - the cyberdemon and spiderdemon. The cyberdemon is by far the most fear inspiring thing i've ever experienced in my not so long 26year life.
(b) They missed the whole 'from hell'. I guess they were afraid of the religious activists. In the end they settled for the whole genetic experiment gone bad plot. Lame.
I do not think that the movie did the game justice. It could have been alot more frightening.