It's funny, the Apple/Mac crowd is different... Apple can come up with new products/software that are barely compatible with the past, or not at all, and the Apple Fan Boys don't seem to mind at all.
Apple doesn't come up with stuff that's barely to not at all compatible with *recent* offerings, though, and that's the big difference. The Apple stuff is just always in a slow state of transition, and they manage transitions well. Hell, the Mac line is on its THIRD chip architecture (Motorola 680x0, PowerPC, Intel) and also managed to completely change its underpinnings from the proprietary start of Mac OS to the Unix base of Mac OS X.
I've been a Mac user through all of it. Can I run things from 1986? No. But when the first change, to the PowerPC architecture, came about in 1994 they made it pretty easy to make the jump - Developers could compile a "fat binary" that worked on either architecture, and the OS would translate the older programs to run anyway, albeit without the speed gains inherent in the new architecture. By the time you couldn't buy a 680x0-based Mac any more, any software that was still being supported had been switched over.
In 2000 or so when Mac OS X shipped, the original Mac OS API had been morphed into "Carbon" which took 90% of the OS calls that were originally available and kept them. The ones that they got rid of were the ones that weren't possible to put into a form that would work with things like protected memory, preemptive multitasking, and other modern OS features that Mac OS X had. So, developers had to go through their programs in the last couple of years before OS X debuted and re-jigger the parts of their software that used the remaining 10% so that it was compatible. In addition, you could run Mac OS 9 within Mac OS X (aka "Classic") after it came out so that you could still run the old software that hadn't been updated yet.
When the Intel machines were introduced, it was similar to the PowerPC transition - Programs could be compiled to run on both architectures, and a system called "Rosetta" was included in the OS to allow the newer machines to keep running programs that were compiled for the older ones.
They don't keep things compatible two levels back - When OS X came out, programs compiled only for 680x0 chips no longer worked. When the Intel machines came out, they no longer ran Classic. And now, Rosetta support has been dropped as well. However, with the time span between all of these upgrades, there was PLENTY of time to upgrade software to remain compatible and to translate older documents into newer formats if necessary.
That's why the Apple users don't squawk too loudly - We get plenty of new features to make up for the minimal time spent to update our software over time, and there's never a major shift to how things work. Microsoft, OTOH, will completely upset the apple cart in a single upgrade and **** off all their users. That's where the difference lies.