Over 10% and 3 or more seat? Fair enough, I can take that bet. They may well take 3 seats, but they won't get 10%.
What progress is Ed making as a leader? His impact on the Swindon council elections was a direct cause of the Tories increasing their majority. The people simply aren't taking to him, and don't see him as a leader. In many ways it's a similar problem to Gordan Brown, but at least Gordan carried a certain gravitas even though he wasn't all that likeable. Don't get me wrong, I think he's actually a decent chap, but I would hate to be a Labour supporter looking to him for inspiration.
Newark is an interesting one. By-elections are extremely difficult to predict, especially after the recent wave of UKIP publicity. It could be that the voters decide to give the Tories a bit of a kicking, especially because their last Tory turned out to be an arse, but...
I reckon the Tories will win with around 20,000 votes. Labour may claw their way up to 15,000 if they put up a real fight. UKIP around 10,000. But again, who knows with such things?
I don't think it will have much of an impact on the general election whatsoever.