We already know that Labour are planning to raise taxes by £15 billion (they voted for the Government's plans for a further £30 billion of fiscal consolidation - spending cuts or tax rises - over the next few years and Ed Miliband has said that half of it should come from tax rises). But they won't say which taxes are going to go up.
Today, we got our first hint. Ed Balls refused to rule out reducing the level at which people start paying the higher 40p rate of income tax.
The higher rate is meant to be paid by people who are wealthy. At £42,385, it's already too low (and we have to take some of the blame for that - in the first few years of this Parliament we weren't able to increase it in line with inflation because of the pressing need to get the deficit down). Someone living in London with an income of just over £40,000 a year may be earning more than the national average, but they're certainly not wealthy.
Now the economy is recovering, we've said we can increase it to £50,000 in the next Parliament to help such people; Ed Balls is clearly looking at reducing it, hitting people who earn more than the national average but certainly aren't rich.
So this was a day when the choice at this Election became clearer: a growing economy and lower, fairer taxes under the Conservatives versus a risk to the recovery and higher taxes under Labour.