Canon G11 or XS DSLR?

The XS is $529, the G11 is $519 here in Canada.

I currently own a Canon SD870is, and I intend to keep the Elph as a pocket camera for when I don't want to lug something big around. But there are definitely times when I wish for more control, better image quality, and the chance to stretch my photographic abilities.

Which way would you lean? The idea of manual controls and better images appeal to me. Size not so important, as I already have a small cam for discreetness.
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