Backward compatibility is something no developer is fond of :) It is an example of a necessary evil. However, for customers and users it is a huge boon. Backward compatibility is necessary because of the largely-for-good changes that happens as a software becomes more mature. And because you can hardly get things right the first time around. There is no way one can avoid incorporating backward compatibility if one wants to really make a living out of selling software. Therefore, instead of an afterthought, backward compatibility should be in the plan of things while you are developing software. One must create a framework which enables one to incorporate backward compatibility easily into future versions of the software. Never shy away from it, it is something one must actively pursue.
I recently installed the Windows 7 RC1 on my now-very-old Fujitsu S2020 laptop. Windows 7 won’t recognize the graphics card (ATI Radeon IGP 320M) or the sound card (Sigmatel C-Major Audio) in it. However I was able to install the Windows XP drivers in compatibility mode and both work absolutely fine, thanks to backward compatibility. (Aero of course doesn’t work, the graphics card is really old :()
