I'm sure this wasn't an issue in beta 5 version, but if you load a tour in portrait mode on the iPhone 4 then rotate to landscape the simple thumbnails are cropped top and bottom again, happens in safari and Mercury. Only an issue when to tour is loaded in portrait mode, not an issue if the tour is loaded in landscape then rotated to portrait.
Seems the orientation of the thumbnail plugin isn't being picked up when you rotate the phone. Also still crops the bottom thumbnail on the iPad 2 in safari.
Test link to tour: www.irisimage.com/360-degree-gallery/ptp2-rc1-test