Not wanting to sound disbelieving, or dispute facts, It is not all that easy to get out of a Cessna in flight.
That is certainly not unbelievable! Its not all that easy to get out of a Cessna on the ground either!!
(It's ok I'm not having a go at the beloved Cessna though Jim - I still hire my trusty little 152 against the added comfort of a 172 or PA28!)
In all seriousness though, an interesting incident which will probably spark a short lived debate on GA security procedures for a time before this gets filed away under its proper heading of 'freak isolated light aircraft suicide'.
Ryan