Well, its certainly put the cat-amongst-the-political-pigeons ...
... Gordon Brown announcing his resignation (as from September?) has frankly blown wide open the possibility of an alternative to any Con/Lib arrangement.
And to all those who would argue that the Party who comes second in a General Election can't lead a working-Government, then I'd simply ask them to look at Sweden (or many others continental examples) and its 2006 national election result ... do the Tories really believe that Fredrik Reinfeldt has no legitimate right to be leading the Swedish Government?
I'm not making the 'political' argument for, or against, any Lab/Lib arrangement - but to argue, as many appear to be doing, that such an arrangement is somehow not constitutionally viable (here in the UK) is just plain wrong.