I'm sure we'll eventually learn more about the reasons why Dalton McGuinty decided to jump ship. But it's worth pointing out how his move looks to completely undercut his own party.
After all, Ontario's Libs have spent nearly a decade branding McGuinty as the dull but reliable Premier Dad - and followed up on that by echoing the Harper Cons' rhetoric about stability. Which makes McGuinty's abrupt and not-particularly-well-explained departure an especially striking development.
Now, the Ontario Libs will have to set up a leadership campaign and debate what exactly they stand for as a party before choosing a new leader. And all this in a minority legislature (and a time when the Libs were already falling behind two opposition parties in the polls).
Which is to say that having already gone out of his way to lose the confidence of the labour movement, McGuinty has effectively trashed the message which helped his party cling to power last year. And that means that whoever succeeds McGuinty shouldn't count on staying in office for long.
[Edit: fixed wording.]