Why don't Google search results in UIWebView launch webViewDidFinishLoad?

This is without a doubt a more general problem with web pages, but it is easy to demonstrate using Google content.

When you enter some search criteria on the Google homepage, the results do not call the webViewDidFinishLoad method . The same problem occurs when the Google color logo is replaced with some images associated with the feature page.

I suspect the page is not fully loaded due to some javascript or ajax code, so is there any way to detect this?