According to me, If a lender forgives worth of the principal on your debt, it must report the amount to the IRS via a form. So, for example, a lump sum payment of $2,500 to settle a $4,500 credit card bill will mean you'll likely have to pay tax on an additional $2,000 in income next year.
You seem to be under the impression that this is a US site (I guess that because you mention the IRS) - it is an Irish site so the IRS has nothing to do with it