When the terrorist Bassam announces the plan, the murmurs of assent from the group include the audible word "aywa." This word for "yes" is unique to the dialect of Arabic spoken in Egypt and identifies the speaker as an Egyptian.
The trivia items below may give away important plot points.
When Gibbs is dreaming at the beginning of the episode, he dreams that he walks in to the morgue. He walks up to the table with the body bag and opens it. Kate is in the bag with a bullet hole through her forehead. This is, in fact, the way Kate is killed at the end of season 2.