Okay, I admit, coming from me this is weird. I'm usually the guy responding here to every new regional board request with a comment like: "Just what TER needs! Another dead board!" I even shoot down suggestions for a board for my own state because I know it would be dead.
However, in this case there may be a good argument for one or more new regional boards for California. With the shutdown of that other site, there has been a huge influx of new members. The TER San Fransisco regional board has 584 posts in the last 5 days. In the 90 days prior to that it had only 129 posts! The SF board here was a slow board because the other site was popular in SF. Now that it's gone, SF's board has exploded. Of course the large number of posts are not going to last forever, and things will probably settle down in the next few weeks. 100 posts per day will not be the norm, but I'm guessing 100 posts in 90 days won't be either.
Anyway, there are many other areas of California that were covered by that site, besides SF, and the providers and hobbyists from that site are looking for new homes. Earlier today a provider asked on the newbie board about Sacramento. Personally I don't think Sacramento warrants it's own board but perhaps TER should consider a "California Central Valley" board, and perhaps an "Inland Empire" board (covering San Bernadino, Riverside, etc., and maybe a "California Gold Coast" board. Gold Coast is actually listed as a city option for reviews but it has no discussion or ad board.
Another option is just a "California other cities" board, that would cover all parts of CA besides SF, SD, LA, and OC which already have their own boards. This would of course be different from the existing "other cities" board which covers the world.
Maybe add just one discussion boards but several ad boards? Things for admin to think about, but I know the wheels usually turn slow here. In this case this is something you should jump on fast to take advantage of the influx of new members and make them feel at home.