Will a $300 price cut do for RIM’s struggling Playbook tablet what it did for HP’s defunct TouchPad tablet? Canadian retailers are slashing prices ahead over the weekend in what appears to be an attempt to clear space before the holiday season rush starts in earnest. It’s pretty clear at this point that the Playbook has failed to spark any real interest among consumers, which probably has the retailers who purchased any of the 700,000 devices that have been shipped wondering what to do with them. Engadget spotted a massive price cut taking place at four large consumer electronics retailers in Canada through next Tuesday, perhaps in hopes of getting TouchPad-like interest in the product simply just to get it off its shelves. After all, the busiest season of the consumer electronics world is exactly a week away, and retailers would probably prefer to stock up on things that people will actually buy this holiday season. And given the interest in lower-cost tablets like the Nook and Kindle Fire, it’s hard to justify charging$500 or more for a tablet that isn’t an iPad or even a Xoom.