I have played the beta and all this week on dial up so I will reveal my experience. First off, if you can really get a 56k (v90,v92) connection then you will actually be doing better off than me. I can only connect most of the time at 26.4 (sometimes I'll see 28.8) which is really only a v34 connection. I'm assuming it is because there are extra analog to digital conversions along the phone line. You can only have one conversion to get I believe above a 32k connection. I have no phone noise that I can tell so this must be the case. Your experience may be much greater than mine if you can connect at a higher speed than me.
No, I do not believe the OP is trolling. I myself live in the USA in the Appalachian mountains and can only receive dial up or satellite service. Even though I'm only a few miles away from the interstate I cannot get DSL, Cable, WISP, or a cell phone signal. Also, all these people saying how it will be impossible to download the client is beside the point. There are ways to download large files away from home. Even though I have both satellite and dial up I downloaded the client away from home and copied it to both computers in the house. Now I can use my satellite to download patches and dial up to play the game. The fact is that telephone companies only care about the most bang for their buck and will not expand their network to rural areas. There are two telephone companies that service my county. One is actually going to rural areas. The other is Verizon which will not expand their service. They have a hard enough time maintaining the old copper lines for the landline phones. Guess who I got...Verizon. Since they own the area the other company cannot provide service to me. They will also not work with other companies that want to provide other means to provide internet to the area. They refuse to provide the backbone.
Your best bet if you cannot get a 3g cell signal would be a one-way satellite service. I used one to play WOW and RIFT and it worked great. The ping time was between 600-800ms. Now that may sound awful to most but it was actually very playable. However, the only provider of one-way satellite service I know of in the United States went bankrupt and I'm not sure if they are ever going to come back. That's why my only option was to get a two-way service like Wildblue. You "can" play SWTOR on Wildblue but the experience is not enjoyable. Even though you never lag out or have lag spikes like dial up, I tried it in the beta and my ping time was 1100-2300ms. Now when Wildblue starts to use their new satellite perhaps they will remove their DAMA shaping (I think that's what it's called) and pings will go down to 600-700ms like people say it used to be back before 2006.
Ok, I'll now give my experience on dial up this past week. Again, if you can connect at a higher speed than my 26.4k then your results may be superior. First off you will need patience. While most of the time my ping on dial up goes between 2 and 3 bars on the latency meter (225ms - 285ms, sometimes I'll actually see below 200ms) it does frequently shoot up when I get close to several players. I assume once my client gets the data about what them and their companions are wearing the latency goes back to normal. If I go to an area like a heroic area or an area like Lord Grathan's estate on Dromund Kaas where a lot of players are doing their quests it does get unplayable as my ping can shoot up to 5000ms-25000ms+). After I stand still for a bit it does eventually go back to normal after my client gets all the data. Sometimes it will do it several times if there is a lot going on. Sometimes my connection cannot recover and I have to relog to fix the problem. This is where the patience factor comes in. If you are the kind of person with limited patience then try at your own risk. Next I'll give some examples of common areas in the game with my experience. I have mostly only played on the Empire side so I can only give experiences from there.
Korriban - Was fine for most part. Few lag spikes.
Imperial Fleet - I have mostly had no trouble here. Of course latency can spike if you run into a lot of people. It has also spiked after getting off the elevator.
Black Talon - I have only run this with my partner so far (which is also on dial up, seperate modem and phone line). It was our characters with our companions. The flashpoint works pretty flawless except it can spike riding the elevators for some reason.
Kaas City - Spikes frequently if there are a lot of people around. Especially if the craft and trade area has a lot of people. Most of the time my connection recovers without having to relog.
Dromund Kaas questing - Heroic areas were a problem, managed to still play and get through them. Lord Grathan's estate was the most troublesome area. Still was able to do all quests on the planet and move on.
Your own starship & space missions - I have only done one space mission so far and it worked flawlessly.
I can keep posting new areas once I go to them.
I know no one will read all of this unless they are in the same boat as me. Hopefully I have helped anyone looking to play SWTOR on dial up.