Fix bad JSON link and inconsistent link formatting.

examples/Notebook/What is the IPython Notebook.ipynb

@@ -2,7 +2,7 b''
  "metadata": {
   "celltoolbar": "Slideshow",
   "name": "",
-  "signature": "sha256:ad9cb95b14212dbf9fc8ecafa475d0e368e4cb7c7306b89628b500e7e40068b6"
+  "signature": "sha256:86e99da10fb4a123108149196f182861fa434fb59520b256405c6052601c2486"
  },
  "nbformat": 3,
  "nbformat_minor": 0,
@@ -166,11 +166,11 b''
       "* **Heading cells:** 6 levels of hierarchical organization and formatting\n",
       "* **Raw cells:** Unformatted text that is included, without modification, when notebooks are converted to different formats using nbconvert\n",
       "\n",
-      "Internally, notebook documents are **[JSON](http://en.wikipedia.org/wiki/JSO) data** with **binary values [base64]**(http://en.wikipedia.org/wiki/Base64) encoded. This allows them to be **read and manipulated programmatically** by any programming language. Because JSON is a text format, notebook documents are version control friendly.\n",
+      "Internally, notebook documents are **[JSON](http://en.wikipedia.org/wiki/JSON) data** with **binary values [base64](http://en.wikipedia.org/wiki/Base64)** encoded. This allows them to be **read and manipulated programmatically** by any programming language. Because JSON is a text format, notebook documents are version control friendly.\n",
       "\n",
       "**Notebooks can be exported** to different static formats including HTML, reStructeredText, LaTeX, PDF, and slide shows ([reveal.js](http://lab.hakim.se/reveal-js/#/)) using IPython's `nbconvert` utility.\n",
       "\n",
-      "Furthermore, any notebook document available from a **public URL on or GitHub can be shared** via http://nbviewer.ipython.org. This service loads the notebook document from the URL and renders it as a static web page. The resulting web page may thus be shared with others **without their needing to install IPython**."
+      "Furthermore, any notebook document available from a **public URL on or GitHub can be shared** via [nbviewer](http://nbviewer.ipython.org). This service loads the notebook document from the URL and renders it as a static web page. The resulting web page may thus be shared with others **without their needing to install IPython**."
      ]
     }
    ],