this person just had a very similar problem. Not sure if the cause is the same.
What I would try is open up the BLOG.JS file in the root of your blog. The very top line is this:
// global object
Delete that line -- it's not needed. After deleting it, restart your blog by making any change to the web.config file (add a space, etc).
Then see if things start working. You can check that URL above. It should start returning content, instead of a blank document.
@rburkhal: I would make try doing the same thing to see if it helps.