This is the awesomest news for the day. It is so much more than a tool purely for the scientific community. I use it for quick fire data analytics codes all the time. Especially when coupled with pandas and matplotlib. pandas can output data in a tabular format directly onto the HTML notebook.

If creating forms on the same was a bit more simpler, then it would be biggest boon to a data analyst since excel sheets...dare i say. It would lead to quick fix applications, rapid prototyping for reporting applications. And it can be hosted and shared directly: http://nbviewer.ipython.org/