Each delegation gymnast brings one personal coach at USAG expense to China. They may also bring second coaches, family members, etc. at non-USAG expense so long as they can be accomodated.
During team preliminaries and finals, there will be one male and one female coach on the floor chosen from the competing team members' personal coaches plus Marta.
For AA and EF, generally the floor credentials (I'm not sure if that's the right word for it) are switched around between the gymnasts' coaches so that they may have their personal coaches with them.