I bought this domain a few years ago and since put up a image hosting site. I recently had to pull the site down because I had no time to manage it anymore, but when I did, I had about 200 registered members and about 50 pageviews a day. It is currently a PR3. Do you think this domain has any value in and of itself?

I'd say it was valuable if it were imagehosting.us.

Exact match domains always have value. But since it's not. I'd say not so much. Maybe some branding vale. for us web geeks but to the average internet user searching for "image hosting" this wouldn't help much.

Just the domain without traffic it has not value. If you develop it though, it can.