From http://bugs.debian.org/529702:
Reproducible with latest 6.5.4-9Some recent update to imagemagick seems to have broken the ability of the -delay flag to loop through a list of images. The specific manifestation of this I've noticed is that formerly if I ran, eg. "display -delay 100 pic.jpg" it would just sit there refreshing the image over and over, which was great, because I could use it to turn my digital camera into a webcam. But now it just shows the image once and then exits, and I don't see any new options in the man page that could help me adjust this behavior. Downgrading to 7:6.3.7.9.dfsg2-1~lenny1 [ImageMagick version is 6.3.7-9] restores the former behavior.
Was this a deliberate stylistic choice or a mistake, and if it was deliberate, is there a flag (or could a flag be added) to restore the former behavior?
