Updated README.

README.md

@@ -1,22 +1,39 @@
 ## The CometD Project
 
-### CometD client for NodeJS
+### CometD NodeJS Client
 
-Adapter code that allows the [CometD client JavaScript library](https://github.com/cometd/cometd-javascript) to run in a NodeJS environment.
+This project implements adapter code that allows the [CometD JavaScript Client](https://github.com/cometd/cometd-javascript) to run in a NodeJS environment.
+
+The adapter code exports an implementation of `XMLHttpRequest` so that the CometD JavaScript Client works in NodeJS as it does within a browser environment.
+
+WebSocket is not (yet) supported.
 
 ### NPM Installation
 
+Firstly, you need to install the CometD NodeJS Client:
+
 ```
 npm install cometd-nodejs-client
 ```
 
+The CometD NodeJS Client does not depend on the CometD JavaScript Client; you need the CometD JavaScript Client to develop your applications.
+
+Therefore, you need to install the CometD JavaScript Client, version 3.1.2 or greater:
+
+```
+npm install cometd
+```
+
 ### Usage
 
 ```javascript
-// Run the adapter code.
+// Run the adapter code that implements XMLHttpRequest.
 require('cometd-nodejs-client').adapt();
 
 // Your normal CometD client application here.
+var lib = require('cometd');
+var cometd = new lib.CometD();
+...
 ```
 
 See [here](https://github.com/cometd/cometd-javascript/blob/master/README.md) for an example CometD client application.