Up and Down the Python Data and Web Visualization Stack
nbviewer.ipython.org
nbviewer.ipython.org
I may be biased, because I wrote the hacky IPython integration, but I really love the graphs produced by nvd3.
I would also recommend running the notebook live- some of the interactivity/plots don't work via nbviewer.
Damn, haven't learned enough ggplot2 before it expires.
IPython is two separate pieces - a core kernel, and a frontend that communicates with it via a published protocol. Anybody can design any client they want to interact with the kernel. The notebook interface in the browser is definitely the richest, in terms of features.
http://spaceli.wordpress.com/2013/10/04/add-vim-key-bindings... (the post was for iPython 1.0, but it seems to still work with 2.0)
This feature alone made me 10x more excited to use iPython notebook as a development environment.