We do not currently have any such plans. RadGrid requires its data to be available on the server, so that the export engine can take up the rendered grid markup and export it. When using client-side databinding, no data is available on the server and the export doesn't work.
I have created a PITS item
for this feature request, where you and other community members can vote to influence its priority when planning future releases.
the Telerik team
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