Signed, Sealed and About to Be Delivered

The puzzle has been formatted to the New York Times' specifications and is sealed into an envelope ready to be flown across the country. Wish it luck on its way.

What I've learned thus far:

• There's an informal limit on the number of black squares allowed into a grid.
• Many people don't know what emo is.
• This is fun.

TueNYTX: 6:30. WedNYTX: 7:30. TueLATX: 5:15. WedLATX: 5:30. Oooh . . . pangram.