I understand it to mean that the changes are mirrored. Drop hand written text SQL into the SQL window see a visual representation in the designer and vice versa.
Tamar E. Granor has a good article at:

http://foxproadvisor.com/Articles.nsf/aid/GRANT112 Third paragraph in the 'Easier to work with' section.


Sounds like it is going to be more than a field picker now. Much needed improvement to a great product.