The diocese is encouraging people to return to their pews and continue to stand and sing until everyone has received Communion and the priest has sat down to pray.
The new GIRM says nothing about this; it's strictly an innovation that Cleveland is promoting. If I'm not mistaken, Rome has already said that the practice of kneeling after communion is "laudably retained".
In my diocese (Monterey, CA) Bishop Ryan wrote an article for the newsletter explaining that the stand and sing thing is in the GIRM. As a recent (Easter 2002) convert, I didn't have a reference point from which to evaluate the matter. When I have attended mass outside the diocese the people generally kneel after communion and I happily go along with the locals. I feel better able to reflect on the meaning of the eucharist and communicate with my Lord while kneeling than I do standing and trying to join in the final refrain of the communion hymn.