Two-way data binding to XML file with LINQ?

I can find samples of using LINQ to XML that show one-way or one-time binding to initialize the UI from an XML file.  For example, ScottGu's Digg client.  But I haven't seen a two-way sample that shows how to push changes made in the UI back to the XML file.  Is that possible in SL?  (In WPF XmlDataProvider can do two-way data binding.  See for example: http://www.codeproject.com/KB/WPF/WpfXml2WayDataBinding.aspx).

Thanks,
Phil
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