We just had one in YOW today from a CRJ. I haven't seen the incident report yet (I might have just deleted it - not my fleet) but press reports say the plane made emer ldg due to smoke in cabin.
From what I gather, the main door was opened to allow passengers to rapidly disembark but in the shadow of the LHR episode some passenger in the back opened an emer exit of their own accord. One woman jumped onto the wing and the guy behind her jumped right on top of her breaking her arm and causing her some ankle injury.
There's a few lessons there I suppose.