Be firm on the phone but never rude or sarcastic. Remember, they will be doing you a favour, not the other way round. If they say you can't, then you can get a little firmer, mentioning the 10 day thing, etc.
In future, as a general rule, Apple updates each product line around every 6 months or so. There are no interim small updates, apart from the odd price drop mid-term. So the general rule of thumb is to look at a site such as this one to find out when they were last updated (Buyers' guide) and check for any rumours. The last update was September (PowerBooks) and October (iBooks), some 7 and 6 months ago. Therefore, it was a given that updates would occur around this sort of time frame. Obvioulsy, I understand that many people have to buy their computer at or by a specific time but that's just the way it is.
Good luck to everyone who ordered an old one in the past couple of weeks.