The first interesting news article yesterday was that Amtrak California (Caltrans) will be purchasing 27 new coach cars.
8 of those coach cars will be designated for the San Joaquin. Of the entire purchase, 9 will replace older cars, leaving 18 cars to increase capacity. This is great news, as it shows Caltrans strongly believes that ridership will continue to grow, and the existing 4 car trains (3 coach, 1 cafe) aren't enough. During the summer and on holidays, the San Joaquin gets 5 cars. This new order should allow 5 cars year-round.
What the order also indicates is that there are no plans to introduce business class to the central valley, as no new business cars were ordered. There are also no dining cars being ordered which can be configured to have a business section.
As for increasing runs to 7 a day, the article does not specify if having more cars will make it more likely or not. The order only calls for 2 engines to replace existing models, and not to add capacity in that sense.
The money to fund the purchase comes from 2010 federal grants and a 2006 state bond measure.