It will be implemented as of tomorrow on all Form 4's we submit.
However, at this time the ATF does not have a standard for the barcodes established, nor do they have it implemented. They also have no ETA on when they may implement it and will not comment on rumors.
I don't expect to see a real significant decrease in wait times due to the bar codes, as it's for initial data entry. (The very short part of the wait, the pending to approval is the long part)... but every little bit certainly helps.
The detailed overview can be found here.
http://www.capitolarmory.com/blog/what-is-the-atf-bar-code-system.html