Here's some helpful links for traveling to Korea. I mention it here because for us in the Dallas area, Korea is 13+ hours away. That's a long time to be on a plane...Always a good idea to minimize any boarding or mid-air surprises.
Anyways, these should serve as a starting point for anyone interested in traveling to Korea. Please feel free to add to this list.
Can and Can't Bring List
http://www.tsa.gov/travelers/airtravel/prohibited/permitted-prohibited-items.shtm
Carry-On Allowance
http://www.koreanair.com/local/na/ld/eng/ft/faq/eng_ft_faq_bg01.htm
Checked-Luggage Allowance
http://www.seatguru.com/airlines/Korean_Air/baggage.php
Layout of Typical Korean Air airplane
http://www.seatguru.com/airlines/Korean_Air/Korean_Air_Boeing_777-300.php