What does this actually mean?
It means that the training given is now approved and in compliance with the EU regulations and subject to audit and external oversight.
Will there be a difference in the training they offer,
Probably not, but the details of it will be laid out in a manual!
Presumably someone (the customer) will have to pay for the additional bureauracracy, approval fees, but think of the "additional safety" you now have!
Even EASA considered the ATO requirement over the top for recreational flying, and subject to further committee work, the RTF should be able to Declare its allegance to the Regulation and become a DTO without the expense of becoming an ATO!