I have written a utility to use the object model to walk a site collection and do a search/replace on web parts. However, my one stumbling block is that I had to use the web service GetWebPartProperties in order to get back the actual data in the webpart. For example the Content Editor Web Part stores it's data in CDATA portion of the XML returned. See below.

// <ContentLink xmlns="http://schemas.microsoft.com/WebPart/v2/ContentEditor" />
// <Content xmlns="http://schemas.microsoft.com/WebPart/v2/ContentEditor"><![CDATA[<P>HTML displayed inCEWP</P>]]></Content>
// <PartStorage xmlns="http://schemas.microsoft.com/WebPart/v2/ContentEditor" />

Question: How can I get this data from the object model? I've tried looking at the UnknownXmlElements collection but it comes back with nothing in the collection even though my web parts have content displayed in them.