Bolt Bus is launching an Oakland (West Oakland BART station) to LA (Union Station) route starting tomorrow, 31 October. They've got three trips a day scheduled, and the trip is scheduled to take 7.75 hours. Through Sunday, tickets are $1; starting Monday, they fluctuate between $6 and $9, at least now. (Like airline prices, they change based on demand.) Generally schedules are up 4 to 6 weeks in advance. The Pacific Northwest buses had some schedule shifts in the first six months to adjust for seasonal patterns and for the Vancouver-Seattle route, to take border crossing efficiency into consideration. Bolt charges $1 for processing a single shopping cart. If you sign up, and you're logged in when you purchase, you get a free one-way ticket every eight rides (currently), and the free rides can be used for any ticket, although I don't know if this is limited by route. Plus, you get to board in the first non-Senior "A" group.
If it's the same deal as on the Pacific Northwest buses, there will be seats with seatbelts and lots of legroom, wifi, and two electrical outlets except in the first row and a couple of rows in the middle with removable seats (for disabled passengers).
Now, if they'd only do a Seattle to Oakland route, via Portland...