I want to be able to link to a webpage inside the phonegap webview that loads an external webpage inside the same phonegap webview. If I do this, it loads inside the webview
This seems to have changed, and access origin seems to have no effect. If you're using the cordova whitelist plugin, as seems to be standard. You need to use allow-navigation in your config.xml file. Without this it will open your web browser.
<plugin name="cordova-plugin-whitelist" version="1"/>
<allow-navigation href="https://google.com/*" />
Then you can use window.location = 'https://google.com' to move to another webpage within your JS.
Ahhh.. Found the answer on this question. I had to add
<access origin="www.google.com"/>
to the phonegap.xml file.
In the latest phonegab (1.7) in Cordova.plist there is a Key: OpenAllWhitelistURLsInWebView set this to YES.