The one good thing - The explanation of their powers.
The rocks hitting Ben, the Fire hitting Johnny, the force field exploding on Sue... The only one I didn't really understand was Reed's stretching just from getting his leg trapped under something heavy.
Other then that, this movie is a travesty. It's decent if you cut all ties to it being related to the Fantastic Four and just pretend it's a stand alone story that happens to sort of rip off the Fantastic Four, but it is definitely not the Fantastic Four movie we deserve.
Why is the Thing naked for the whole movie? He may be a rock monster, but still, he should be wearing pants. The costumes are terrible... But at least the Thing looks decent... Aside from lack of pants.
And what's up with Reed ditching his friends for over a year? Reed Richards is Useless. (TV Tropes reference.)