Joost de Valk posted an interesting article about their support policy the other day. Specifically, about not supporting old WordPress versions. Joost comes to an interesting conclusion:
In short: upgrade. I know some developers out there are saying that we can’t “require” people to upgrade, well, I disagree. He compares it to Apple not forcing you to buy a new Mac when it breaks. The difference there is that we’re not talking about hardware. We’re talking about software. Apple regularly asks you to upgrade your system to fix battery issues or other issues.