I made a .nomedia directory on the sdcard and moved one pic to it to see how it worked. Now my gallery is saying there are no pics at all. But all the pics and movies are still on the sd card.
I should also say that yesterday I loaded a movie (had 2 others already), and it took a really long time for the gallery to recognize it. After it recognized the movie, it was quite some time before it would "unpixelize" (for lack of the right word lol) most of the photos.
Edit: I deleted the .nomedia file and all the pictures (and movies) are back in the gallery. I'm going to try it again and see what happens if I wait longer this time. Is there any reason why the gallery would take so long to update after changing something so minor, or is that the norm?