Well here we go again. I work for an airline and can tell you that they do not as @rpmpseudonym says “love to screw over everyone as best as they possibly can.” Ticket pricing is very complex and if you look at the way airlines charge you will see that they operate on a very very small margin. A transcontinental flight with a full airplane will net the airline about $700.00 profit. Total, not per person. If you want to know who is screwing you, look at the government. About 40% of you ticket price is tax and security fees. TSA is another subject that I won’t get into.
As far as should you by your ticket now or later because of a merger, it’s a 50/50 chance. If they merge, it will raise ticket prices. That is the whole reason for consolidation. There are too many seats available now as it is. The chances of the merger being done before November, slim to none. It took Delta/Northwest over a year. I will tell you that once you buy your ticket, you will NOT be charged a fee because of a merger. That will be against the law. In order for a merger to happen, the DOJ will have to approve the merger and they will have to know that passengers will be protected.
I know airline travel is a pain. Passengers in general want a round trip ticket for close to nothing and a zero accident safety record. If you look at a regular advanced purchase ticket, I would be willing to bet you will almost always be able to fly, cheaper than you could drive. Flying is not for everyone and I know families have a hard time justifying the cost. It can be very expensive.
A flight to Japan on either carrier, UAL or CAL will be expensive. Your friend that got a ticket for $550.00 got a great deal. If I had to guess they traveled on a reduced flight day and during the off travel season. November is a high travel month and tickets won’t come cheap. You would be better off going during January when airline travel is down.
Whatever you do, remember that the airline employees are typically understaffed, overworked, and underpaid but will still do everything in their power to give you a SAFE, enjoyable ride.
Good luck and enjoy your trip. Careful planning is always a good idea. Pack as light as you can.