Matt at Innovation One has developed a USB IR transceiver that makes using multiple cable & sat boxes with MythTV much easier and more reliable (they are based in Canada, fwiw). They are seeking a few more Beta testers before they finalize the CommandIR - and were looking to see if any BYOPVR Canadian users was interested.
They do charge a nominal (below their cost) fee for the units, but if you're interested in helping with the testing and have mulitple set top boxes to control and/or want a better way to consolidate your IR receiving/blasting this seems like a good product to check out!