Ed Balls has confirmed that, if Labour wins the general election, then the Mansion Tax will be official Labour policy.
Rich people living in very expensive houses worth more than £2 million will pay £250 a month in this tax, and those who have expensive second homes will pay even more.
The money raised by taxing the rich will be spent on the NHS. It sounds like the kind of policy that no-one could argue with - but it's a lie.
The Mansion Tax has all the characteristics of a tax that people love: it only applies to people who are much richer than most of us - living in their enormous and expensive mansions - so we don't have to worry about paying it ourselves, and we don't have to worry about their ability to pay because they are so enormously rich.
Meanwhile, it's going to specifically fund the recruitment of more new GPs, nurses and midwives, and who wouldn't like more of those?
We don't have to worry about people who have been living in these properties for decades, and therefore don't have the huge income to match their property wealth, because Balls has said those who earn less than the 40% tax threshold will be able to defer paying their tax until they sell up.
He also said that the threshold for the tax would be tied directly to the price rises of more expensive properties, which would avoid dragging more homes into the tax band, so it's always going to be 'mansion' tax for people in their 'mansions' - unless someone changes the rules later.
However, this should not allay your fears, because there's a major issue at stake here: the name 'Mansion' tax is a lie. After a quick search online, we found five properties that fit into the category that Balls plans to tax. And you can judge for yourself whether they qualify as mansions.
1. A two-bedroom flat down the road from the Natural History Museum priced at £2.25 million. One of the bedrooms here is actually only 7'6" wide.
2. A two-bedroom maisonette in Knightsbridge priced at 2.25 million - complete with a tiny courtyard below street level.
3. A two-bedroom flat in a modern block in St John's Wood priced at £2.15 million - with its own balcony.
4. A 1 bedroom flat in Belgravia for £2.275 million. It's just round the corner from Buckingham Palace, but this new build really does only have one bedroom.
5. 1 bedroom flat in Victoria for £2.175 million
Clearly not every property in this price bracket is a mansion for the mega-wealthy. Sometimes they are relatively modest homes - whose price has been inflated by a combination of high population density and foreign investment in the market.
There will be those who argue that many of the people in these properties aren't billionaires with properties around the world, they are working people who have borrowed every penny they can in order to pay a small fortune for the opportunity to live less than two hours from their workplace.
Many are already struggling to pay for their property - without being hit with a thumping £250 bill every month (deferred or not) for the privilege of living in their own home. It begs the question of whether these are the people who need to be taxed into selling up.
Even if you support the idea of the tax in theory, then you have to get over the fact that it's hugely impractical to enforce: who is going to value the property? And once it is valued at a shade over £2 million, won't it immediately fall in value because it becomes so much less attractive, and is suddenly worth £1.99 million again? You're just asking for confusion, unfairness and market distortion.
And once you have put these concerns aside, in support of the general theory that most people with expensive homes have room in their budget for a £250 a month tax, you have to agree that naming it a 'Mansion' tax is hardy exactly fair.
It's a politically-motivated propagandist move, designed to make us forget that nowadays you can easily spend £2 million on a two bedroom flat in some parts of the country. Balls must be reckoning that using a snappy name as a propaganda tool worked for the 'death-tax', the 'tax on employment' and the 'bedroom tax' - so why not the 'mansion tax' as well.
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