I disagree with the slower than driving. I could take the train from the Valley to downtown SD in less time to drive. The train is a fairly consistent amount of time where driving totally depends on day/time. Leaving the Valley on a Friday afternoon has taken more than 4 hours. On the train, it is very close to 2 hours.
As more fine grained details, from my place in Burbank to my friend's place in Carlsbad was 99 miles. It took longer to drive that than it takes me to drive from Dallas to Austin with is twice as far.
That is context dependent. In Texas traffic outside of the cities isn't that bad and so slow speed trains are much slower than driving. Inside the city of course traffic is a factor, but even then I'd expect in the normal case you get beyond traffic in a short time and then driving is much faster. And of course driving is door to door so you don't have to figure out time to/from the stations, waiting on trains and renting a car (this is Texas - not known for transit though these cities are getting better)
If a train is fast, it's going through uninhabited areas (no stops). The moment you start having relatively frequent stops is when the average speed goes down.
That's not to say we shouldn't have the trains, it's part of the entire transportation package.
The key is you build the transportation framework first, and let the city grow up around it.
If you're "train stop to train stop" LA to SD is great.
I used to use it all the time, it was only faster than driving on Friday afternoons, and even then half the time it would be quite a close cut.
Much, much more comfortable and fun! But not exactly faster, especially when I counted getting dropped off in time to catch the train and getting picked up on the other end.
I just took my beach cruiser with me, and took off. No need to be dropped off/picked up.
Edit: to follow up on your Friday comment. I made the mistake of not driving down on a Friday night, and waited until the next morning. The mistake was not knowing anything about the ponies running that weekend, and half of the LA basin was trying to get there. That was the one and only time I was sitting on the highway where I felt like I was in one of those disaster movies where everyone is trying to flee. I kept looking to see if someone was taking advantage and shooting some b-roll. It took me nearly 6 hours that day.
