Waiting is an issue for ds1 as well, whether it be waiting for my attention, for his favourite programme to start or spending his birthday or christmas money.
It was his birthday last week and he was given quite a bit of money. All he has wanted to do since the moment he was given it, is spend in in the flipping Nintendo DSi shop.
The thing is, we are off to Legoland for a weekend in a couple of weeks time - in lieu of the boys having birthday parties this year. I know when we get there he will want to buy things in the Lego shops, so I have told him he needs to hold some of his money back so he has enough left to get something he really wants. No dice. The thing is, I know that there's going to be trouble, as ds2 is the exact opposite and tends to save any money he's given. He still has last year's birthday money, christmas money, saved up pocket/reward money and its his birthday on Monday as well. He is going to have plenty to spend on whatever his heart desires and ds1 will almost definitely kick off big style when he can't do the same. Doesn't matter what I say to him, he simply cannot bear having the money available and not spending it.
Fortunately, we have recently implemented a rule that he can only go on the DSi shop once a month and only with his dad (we have the password). He spent ten pounds today and won't be able to go back on again until after our trip, so he should at least have some money left to spend.
Actually, now I come to think of it, we were umming and ahhing about getting the SN exit pass when we go, but this thread has reminded me that there's no way he's going to stand in a queue for an hour to get on a ride, so we will need the exit pass after all. 
We have the same problem with lunch times in the holidays as well. He expects his lunch at home at the same time he gets it at school, but the all of the rest of us want to wait for dh to come home an hour later. Now I could make his an hour earlier and give it to him, but in actual fact, I make him wait. I get a constant ear-bashing about how starving he is and how its well past lunch time so I should go and make his lunch etc etc, but he is not going to starve and I think its an important lesson for him to learn. This stance from me is however, relatively new.
I was watching a Temple Grandin lecture last weekend and in it she said that the most important thing we can teach our children is manners, including waiting and taking turns. She believes that a lot of children with ASD 'get away' with rude behaviour because we feel that they can't take on board 'normal' rules, but she disagrees that this is the case. She was basically taught manners, social-rules, turn-taking etc ABA style and still believes today that this has been the single most important part of her education and was responsible for her being able to fully integrate into society. It really made me stop and think. I think sometimes we are too accommodating of ds1, probably because we want to avoid a scene. Working on an ABA-ish principle though - and don't take this the wrong way - but also thinking back to my dog training studies - fundamentally we have to make doing the right thing, more rewarding than doing the wrong one, preferably making our response to their negative or bad reaction completely non-rewarding. If we do this enough times, eventually - in theory - they should start to opt for the more rewarding behaviour.
Now I am still trying to get my head around how to put this into practice properly with ds1, but its definitely food for thought and something I want to pursue. Ds1 is a lovely boy, with a good heart, but he comes across as so demanding and rude and that's what puts other people's backs up. If I can help him learn how not to do that, he's going to find life a whole lot easier and more pleasant.