TurboTax does not say that the IRS is accepting efiles January 5th. They are saying they are accepting them. You file, they hold your return until the IRS is ready - and we don't know yet when that will be. Usually it's the third or fourth week of January, but it's been much later in the past.
TurboTax can only accept and hold your return, though, if all of the forms are finalized both by the IRS and within the software program itself. There are not an awful lot of returns that are made up of solely finalized forms at this point as many are still outstanding.
