When I launch IPython Notebook I can navigate to it and enter code. However, nothing is ever echo\'d back to the IPython Notebook interface.
I know the server is get
I had this problem. I found two ways of fixing it, though your mileage may vary:
I killed the software firewall process.
I configured the notebook to accept HTTP connections from anywhere (with a password and a secure connection, obviously). Details of how to do this can be found on the IPython website.
I don't know why the second one worked. My best guess is that the combination of the firewall and a NAT made connections to localhost look, to the notebook, as though they were coming from elsewhere.