What I understood of Obama's proposal is the opposit of France Fiscal Shield
In France, whatever is your incomes and wealth, you should not pay more than 50% of your income in taxes. I guess the top bracket in France is higher than 50% and there is also a wealth tax. So if you are rich in property that do not bring you lots of cash (Old castle), that may help you. So they are in the process of removing the shield and reducing the wealth tax.
Obama propose that whatever the deduction you can have, whatever is the source of your incomes, if you earn more than a million dollar, you should pay at least the same rate than middle class americans. That make sense to me.
People may start playing with their money so that they do some do not register as income but If you want to buy a plane, or a house or a cruise ship, you need some income.
I don't know what to think of wealth tax. If the incomes they generates are taxed, why tax the capital? What about the capital of companies?
There is always the inheritance taxes to redistribute them from time to time.