I ran into a similar stuck-loading once (had to reload), and I was only uploading 2048px versions of my images. My thoughts mirrored yours, Brant, and I think I uploaded about a dozen different images. What I was most impressed with was the tag generator; it even generated the tag "Ultraviolet" for a black light image I uploaded. While the rating system is entertaining, I think the tag suggestions it produces can be genuinely useful.