There's an article in the LA Times about the mess at LAX this holiday season. The short summary is that while there are a lot of plans to try to relieve things, it's going to get worse before it gets better, because loads will continue to increase and construction will disrupt things.

I flew out a couple days before the "official" start of the holiday season, on a Sunday night redeye, and getting into the airport was already a mess. I took the flyaway bus, which is usually pretty good about avoiding congestion - they don't have any stops between union station and the airport so they can take any route they want.

Apparently the first traffic light entering the airport had gone out earlier in the day and it caused backups all the way to the 105. Traffic was backed up for about a mile on the 105 at the Sepulveda north exit (google was suggesting to take the south exit and do a U turn), so it took about 40 minutes to get from 1 mile before the Sepulveda ramp to Terminal 1. If I hadn't gotten off the bus and walked across the top of the U I probably would have missed my flight. I could have walked from the 105 faster than the bus.

Later in the week was worse, with rain cancelling and delaying a lot of flights (and no doubt making traffic worse) and a couple incidents with unattended packages.

Some of the fixes that they're planning will help inside the U, like having all buses and transit drop off at Lot C and have a train, but access to there is still limited by the Sepulveda tunnel and traffic on Century. The layout of surface streets makes it difficult to get to the transit center without either going through the tunnel or spending at least a short time on Century. It seems like some sort of transit hub south of the tunnel (or east of the 405) with a dedicated train to the airport could make a big difference in the traffic load trying to get off at Sepulveda, which is probably going to continue to get worse, even with all the changes.