1. What script are you using?
2. How much traffic you get and how much space you use for the images?
3. Where are all the images reside? (/getimg/)
4. Will I be able to use Adsense on the site?
here's my replies to your questions.
1. Sorry this is confidential.
2. You can view the traffic from the statistics. As for space, its not an issue as images will be deleted away after a number of impressions (configurable) and after 1 week (configurable as well).
3. Sorry due to the sensitivity of the users images, I cannot tell you the direct path. Anyway this script uses mod_rewrite.
4. Yes, you can apply for adsense to use on this site, my account was disabled previously due to a proxy site I hosted was not allowed by adsense.