Folks,
This may not be representative for reasons that will become obvious as you read the post...
We flew from San Francisco to New York (JFK) on November 9. Checking in was no problem; however, there were security people who told folks that their carry-ons were too big.
Passing through the security gate and metal detectors were different matters. First, you had to remove coats and all items from your pockets and put them through the x-ray machine. Second, they would not let you pass cameras and film around the machine: everything had to be x-rayed. The x-ray process was slow and it was obvious that they were looking very carefully at the items in the luggage. Third, you were patted down and subjected to a metal detecting wand if you set the metal detecting gate alarm off; i.e., no passing through the gate a second time. Fourth, there were random searches at the boarding gate. This was the first time in this country that I felt the security check was meaningful! Not perfect, but meaningful...
It took us an hour and a half to get from the curb to the gate area.
We returned to SF from New York via JFK in the PM of November 13: it was the day after the AA crash and we decided to arrive 2.5 hours early. Our diligence was rewarded by there being no line at check-in and security having a very short line! BUT it was a very thorough security check. Again we had to pass everything on our persons through the x-ray machine and we were both patted down. I even had to unbuckle my belt so the checker could see I was not hiding a knife beneath the buckle. Even though the line was short, it still took about 15 min to get through security. They were very thorough. I talked to one of the check in people at the gate and she said that in the AM the security check line was two "blocks" long and took over an hour and a half to get though.
At both A/Ps computers had to be removed from luggage and put through the x-ray machines separately. I am not certain why--and in that atmosphere I did not want to question why! My guess is that if you take your dive computer in your carry-on, you will need to have it examined, but I am not certain. Maybe if they ask you what it is and you answer, "A scuba gauge," you will not need to take it out of your luggage???
At both airports there were armed services personnel with automatic rifles and real heightened sense of security. JFK was particullarly tense feeling...
Joewr