Decision to defect
I have been speaking to Quentin Davies (watch the interview here) and what I've been told is that he and Gordon Brown have been talking frequently over a period of months. Remember that Mr Davies has long been at odds with the Tory leadership over Europe, and he was highly critical of David Cameron's decision to break with the EPP (the alliance of conservative parties in Europe), and he'd started to become more and more outspoken on that issue.
He knows Mr Brown because he has served on the Treasury Select Committee, so the two men already had some sort of relationship, and I'm told they bumped into each other a few months ago, got chatting, and that Mr Davies talked about how he admired one of Mr Brown's speeches... and Gordon Brown, ever with his eye on the political opportunity, invited Mr Davies in for a longer chat.
In recent weeks more of those chats have taken place, and finally, yesterday, Mr Davies decided to defect, and to write a letter to Mr Cameron - which reads, frankly, like it was written by Labour Party HQ, though we're assured it was written in its entirety by Mr Davies himself.
This is bad for David Cameron - not because Quentin is a household name (he's not) - but because it gives people the opportunity to hear from a Conservative (or at least, a former one) a list of all the reasons Mr Cameron isn't fit for office. It puts him, frankly, on the back foot.
But will the Conservatives miss Mr Davies as an individual MP? Probably not.