OK, for Schedule 1651, I'm assuming it' the same as every other Greyhound long-haul schedule. So, every 10-12 hours, when the bus comes to a major station, the bus stops, gets refueled, and cleaned. The passengers get off for a while, then once everything is done, they can get back on. Not too bad, no luggage transfer required, which is precisely where people lose their bags. The drivers are changed even more often.
Now, 1683 has a typo in the timetable, it says "NYD-DEN", but it's actually "NYD-LAD", just like 1651. Greyhound has twice-daily transcons now. Another typo, 1682, same problem except reverse direction, it starts at Los Angeles, not Denver. And yet another error, 1679 is a Saint Louis-New York, not Chicago-New York. Chicago-New York is actually 1604, on different timetables.
For 1651 and all the other New York-Los Angeles transcons, I think the "Service Stops" would be Pittsburgh, Indianapolis, Saint Louis, Kansas City, Denver, Grand Junction, and Las Vegas. Should be the same bus the whole way, unless there's an emergency. Not sure if they refuel at Indianapolis or Columbus.
Also, they brought down the fares, it was something around $220 minimum, but now $129 if you catch a good deal from Yield Management. All variable now, of course. If you walk up to the terminal and try to buy a ticket, have fun paying $323! That's how Greyhound's filtering out the "bad" passengers and trying to entice the "good" passengers.
But if I were riding cross-country on Greyhound I wouldn't do it in one go unless I have a Free Award Ticket to Anywhere. Instead, I would stop off at Pittsburgh, Saint Louis, Kansas City, Denver, and Green River, so that I don't have to sleep on the bus at all. No problem sitting on Greyhound, problems come when you try to sleep. It'll cost quite a bit of cash to do it that way, with all the hotels, but it should be fun, though. Especially since it goes through some pretty good scenery for a Greyhound.
Now I'm waiting to see what type of bus they use. Please, not the new sagging seats!