[pier25]

I agree, Windows is much better at backwards compatibility.

OTOH I've found that it's not such a big deal in practice. In my 10+ years as a mac user I've only hit this problem a couple of times. Likewise in Windows I rarely open old outdated software.

That is of course my anecdotal and personal experience.

[nathansoz]

It's not a big deal for consumers. It's a huge deal for STEM departments in universities (a software upgrade for a hundred-thousand dollar machine can sometimes be thousands of dollars).