Grab, grab, grab and nothing in return?

Vince Cable, who used to have a reputation as a bit of an economist before he took office and blew it, would like a Mansion Tax in the next budget, which will make him very popular with Tony B. Liar (unless his charities own all his extra homes). Mr. Cable is very good at saying how much his new tax will cost the victims but not a word on who gets the money or what the victims get in return for their cash.