I've noticed Foursquare has recently started allowing users to upload photos with their check-ins. Is there a way of viewing all the photos uploaded for a venue?
According to the Foursquare FAQ you can only view uploaded (check-in) photos if you are friends with the person checking in or they post them to Twitter & Facebook (and you are friends/follow them). Photos added via check-ins are available through the persons activity, history and checkin detail pages.
Venue Photos are public and can be viewed by anyone on the Venue page.
What is the difference between a check-in photo and a venue photo?
If you add a photo to your check-in, only your foursquare friends can view it (or anyone who can see your posts on Twitter/Facebook if you've posted it there!). If you add a photo from the venue view, it's a public venue photo that any foursquare user can see.