I've often felt Apple's stinginess in the RAM department would bite them at some point. I'm not happy to be proven wrong, but I do feel vindicated.

Sometimes people will reply to this saying it's not a problem, because Apple is more than happy to take your upgrade money. They are, yes, but that's not to say there aren't also problems: not every customer will upgrade, and even those who do upgrade might badmouth the company, which might make friends and family less likely to buy an Apple product. I'm also not convinced Apple likes to disrupt their customers' usual purchase cycle, as that introduces uncertainty in their financial projections to shareholders.