RIM shareholders got a familiar piece of news this week: a lower earnings forecast, and shares plunged as a result. We talk to FP tech reporter Matt Hartley about whether investors are overreacting, or whether it's time to bail on RIM. Plus: All those warnings we've been getting about the North American economy running out of gas in 2011 look to be coming true, as both Canada and the United States put up weak GDP figures this week. Paul Ashworth, chief North America economist with Capital Economics, has the details