Suddenly it all starts to happen.

At 5pm Gordon Brown announces he is going to step aside as Labour leader and signals that talks between Labour and the Lib Dems are to start on the possibility of forming a "progressive coalition".

Brown is gone, at last - that's almost more enough to take in for one day.

And then up pops William Hague who makes an offer to the Lib Dems of a referendum on proportional representation. That gives you a flavour of how hungry they are to strike a deal which gets them in to No 10.

I'm told the mood at today's 1922 committee when David Cameron set out to his MPs what was going on was positive although there was some sucking of teeth when Mr Cameron outlined his offer of a referendum of the alternative vote. But they backed their man.

Yet the signs are this is as far as the Conservatives will and can go, preferring opposition to pressing ahead with something they do not believe in.

All day the news appeared to suggest that the Tory/Lib Dem talks were moving along positively and an announcement was due soon. Though the pundits may have been misreading the situation and critically not taking in to account the more complicated instincts of the two parties which are critically to any breakthrough.

So Gordon Brown's intervention was a potential game changer.

Yet the prime minister's announcement is already causing unease in the Labour ranks. Former minister John Reid has been on TV warning the progressive coalition idea is disastrous. He says David Blunkett backs him on this - there is evidence of support locally too. There seems to be some disquiet about whether the Prime Minister had revealed his plans to his own cabinet or not.

And is the leader of the Labour party the same thing as the prime minister, you have to wonder...

Although he is quitting as leader, is Mr Brown really stepping back or will he play a backseat role? It does seem strange that he, and not his successor will oversee the coalition talks. The prospect of a new prime minister who had not won popular support through a general election seems outrageous.

The prime minister appeared to be acting honourably in stepping down, but the risk is that voters may conclude that self-interest is now emerging before the national interest.

But there is another irony too. Anybody involved in negotiations at work or even in local government know that it can take weeks to agree deals between two sides. Yet on this most complicated issue of forming a government we expect a deal within a matter of days.

The issue needs to be resolved soon, but all sides should be given time to put together a package that is at least robust, as they hint they want to do.

The Lib Dems are swimming in shark infested waters and after today's events I can see this blowing up in their faces.

Because the biggest issue of all is this.

The Conservatives won the most seats, and they won the most votes. Any sensible coalition needs to revolve around them. That seems fair.

We have been told that the creation of a stable government is key to the coalition talks.

But failure to conclude a deal could signal the death knell of any hopes of PR if this is a taste of what's to come. Any coalition must be seen to work if the public are to be won over this kind of haggling.

Which is why despite the talk of the rainbow alliance, tempting as it may seem to those on the left, Nick Clegg's only real coalition choice this time around, if he is serious about coalition government is the Conservatives.