The links provided by TheWinner don't address your question at all, and I don't believe there is any change to the tax position of ISAs proposed.
However, there are already areas where ISAs are taxed, or effectively taxed, and you may be confusing it with these:
quote
Although dividends from UK equities will no longer receive a 10% tax credit, investments sheltered within an ISA are still free from income tax. You do not pay tax on interest and bonuses. There is also no income tax liability on withdrawals from your ISA.
Interest paid on cash held temporarily in a stocks and shares or insurance ISA will be taxed at a composite rate of 20%.
unquote
Neither of those is new.