Doc,

you are allowed a bag and a "small personal item" with laptop okay as long as the size and weight are in line - hclee01 was kind enough to post the details.

You may not have problems with too much weight in a bag departing the US - I've yet to see it enforced leaving the US.

HOWEVER, they very strictly enforce both dimensions and max weight per bag (both carry on and checked) coming out of Asia.