The astonishing thing is the 3D rendering of the human body from the skeleton on out to the skin - viewable in whole, in layers, in cross-section, in dissection, and from any angle. The level of detail and utility is so much more impressive when you realize this is all done in the browser - no plug-ins, no downloads, nothing to install. (Firefox only, for now).
The applicability and implications go beyond science, medicine, and education of human anatomy. This type of utility delivered through a browser will do amazing things to advance other areas such as architecture, gaming, manufacturing, finance, and more. Certainly there are desktop applications that these industries use for visualization, but it's the power of browser ubiquity that will make rich information more accessible and engaging to more people.
If you don't have Firefox, or would rather just sit back and watch the awesomeness, check out the video of their presentation and advance to timestamp 01:17:00.