Yep, it's clearly some OS4 modules running on top of an older install (presumably 3.5 or higher.. even though there seems to be a system partition called "WB2"), but I wouldn't expect anything else unless the screenshots came direct from Hyperion. There seems to be some sort of iconify hack on there as well, an iconify gadget on some of the windows doesn't fit the titlebar properly.
Mind you, the backdrop picture is gorgeous.
Chris
