I've been work with getting data back from a web service with the October Release and using the Core Bits. If I try and return a datatable, I have been getting an error. I did some checking and I found that the datatable serializer is in the CTP dll, so this has been a frustrating situation. I did some reading and some additional checking and it looks like the only way to return data from a web service through a web service is by creating a strongly typed set of objects. I've been creating a Generic List<T> and then calling a .ToArray() when I return the data. if you have some additional suggestions, feel free to add them as a comment in this message.
Originally posted at: http://morewally.com/cs/blogs/wallym/archive/2006/10/29/462.aspx