Anyone that finds this surprising clearly isn't very switched on.
A 20% VAT rate is likely to be just ONE of MANY tax rises. We have an unbelievably huge budget deficit that has to be brought under control. I voted for the Conservatives under the *full knowledge* that I would end up paying substantially more tax than I am right now. And this shouldn't be surprising. I'd rather pay a bit more tax for a few years if it means this country doesn't become a third-world country. Just look at Greece if you don't believe what can happen to a country with such money problems.
Of course, in 10 to 15 years when the budget deficit is back to normal levels... I am not expecting the government of the time to lower the VAT to 17.5% again. I totally realise that something like this is, pretty much, going to be a permanent change.
It's not Con-Lib's fault. It's Labour's fault. This is how the political system works in this country. We have a period of time where Labour, the big spenders, spend all the cash reserves we have. Then we have a period of time when Conservatives fix all the problems Labour caused in their previous reign of power.