Hmmm, looks good, i will be testing some uploads to give a better view
Edit:
Looks good, nice and useable
Couple of things that i think should be included, User accounts is a must, if this is placed on a popular websapce, the "Gallery" would become overloaded with images and it would be impossible to find your own image if you have lost the code for it. Are there any moderation features for new images? These sites could be overloaded with innapproprite content unless you have some way of checking new photos, and ways to block/ban people. another thing that could be implemented is a random image on the homepage, say if you had an option during upload whether the person minds the image on the front page, and select one from random, because it does seem a little plain.
Hopefully those suggestions give you food for thought