The media is making a great deal out of Speaker Pelosi's call to postpone the State of the Union over farcical security shutdown considerations. Even assuming that Pelosi can block the address from taking place in the House chamber, there's no reason it shouldn't go forward anyway.
Having the State of the Union in the House chamber is a tradition, but it's certainly not mandatory. The Senate chamber might be a challenge at 80 by 113 feet, but with gallery seating, not an impossibility. And there are other government forums that can be used.
Washington D.C. has plenty of locations that can be substituted for the House chamber, but the State of the Union must go on..