As I understand it and as I am seeing in the online shops it is mostly the flavored juices (can't speak for DIY as I have never done that). All the fruity stuff that they say cater to the younger crowd. But from what I am seeing online, you can get Tobacco based juices in California still. But they have to be mostly tobacco with a hint of something else to just slightly flavor it.
I stocked up before the end of the year so I have plenty. But I have been going online to just see what is out there. Some of the online shops have put up check where they see you are from California and you get a California only list of juices. Again all Tobacco based. Along with Menthol as well I see. I am not a fan of menthol/ice. But I usually have one bottle on hand to mix it up from time to time.
Even saw one sight that didn't appear to have a California only option only to see that it wouldn't actually put my order through once it got to the shipping portion of the site. So they are all doing it a little differently it appears.