I'm running 10.6.8 (Snow Leopard) (posting from it, in fact), so this decision affects me.
I realize software companies have to pull the plug sometime, but this decision is a hassle for me. Already Apple has stopped updating Safari. I moved to Firefox which was so buggy and crash-prone I got frustrated. Moved to Chrome, which has worked well. This puts me one step closer to no browser.
My gripe is that my hardware is working perfectly well. I have no REAL reason to buy a new computer except for the fact that software companies force me to. This machine (a Mac mini) is working absolutely perfectly.
I face the same issue with Itunes, which I can't update because the new version requires a version of OSX I'm not running. Furthermore, not only has the latest version of OSX gotten pretty 'meh' reviews, it's pretty clear installing it on older hardware takes a working machine and turns it into a deadweight - the latest OSX works terribly on a Mac Mini purchased in 2010. (The charts show it is possible, but the user reviews all say "this was a mistake").
Not sure what I'll do with this machine - make it into a media box or something, or flash it and install FreeBSD or something. But I'm annoyed - this hardware works just fine; I have no reason to go out and splash down another thousand bucks just because software companies decide to give up on it.
Finally, connect the dots, people: each year software companies give up on old hardware a bit faster. In another decade they won't bother supporting anything other than machines sold that year, and we'll have moved computing hardware into something disposable, which is ecologically ridiculous. Already they've got you throwing out your old iphone every two years so you can have the latest and greatest - imagine how rich you'd make the magnates if you threw out your desktop every two years, too.