Photo Histing Web-sites
Has anyone heard of shootproof?
http://www.shootproof.com? If so, how do they compare to smugmug?
Never heard of them. Their website is kind of thin on info. After a very quick look at it, it seems like if your priority is selling, some areas of ShootProof may be better than Smugmug. But Smugmug is far deeper and wider in its feature set and may be able to handle more edge cases. Also, where ShootProof prices you based on the number of images, Smugmug is unlimited photos and unlimited bandwidth.
If you're thinking about ShootProof, you might also want to take a look at exposure manager.com which is a much older and well-established site that is also focused on sales, with a deep and detailed feature set like Smugmug.