Hopefully JS/WebGL will help enable a client-server model for medical image analysis analogous to AWS/Hadoop/etc. JS has been successful not only for its ubiquity, but also because it - warts and all - hits a development sweet spot. Right now the big open source med image projects (MITK, Slicer, etc.) are almost all C++, so the barrier to entry is too high for some people who might be able to contribute substantially within the JS sweet spot.
Here's a really neat step in this direction: http://www.nmr.mgh.harvard.edu/~rudolph/webgl/brain_viewer/b...