[BirdOPrey5]

Although not technically part of vBulletin I use a free php script for users to upload images to a photo contest I used to hold. The page is still up at:
http://www.juot.net/forums/photocontest.php
and the script I customized is found at:
http://www.solitude.dk/filethingie/

This will let your users upload images (or any file types you allow) to your site, and you could even combine this with a custom bb code like I did so users just need to put in the filename between custom bb code that auto fills in the img tag and file path... I use [PCE] and [/PCE] for Photo Contest Entry... as is it won't integrate into vB with all the features you want but it's something and free and available now.