Yep. What probably happened is that your browser cached the old image reference, so even though the new one was up on the wiki, you were still seeing the old one. Shift + reload, or F5, should allow you to see the updated image.
And as Oreo said, just go into the Edit tab and add in
[[Category:Delete]]on all the images (or pages) you want to get rid of. One of us will empty the trash bucket the next time we do a sweep.