sidefx:BraaiGuy: Any plans to add Wheedle?
I'm guessing Wheedle don't have an API and won't for a while, making this non-trivial.
Also it would need to be done as a seperate site I believe (unless you can get trademe to agree to it) The Trademe API ToS say:
You may not combine Trade Me content with content from other online marketplaces without our express permission.
Oh dear. I forgot about that, it makes things trickier.