No, I would blame Apple, but relying on browsers you will have a higher failure rate. That's not even questionable. You have 2 points of possible failure. OS itself and browser code. If you don't rely on browsers then you only have OS issues. It's not rocket science.
As for Apple, they are imbeciles who have never tested anything properly ( they only seem to test their own programs running on their own OS and even that they get wrong way too often ). Going back 10 years or so, I can recall them breaking numerous programs, mostly through quicktime; Maya, Lightwave 3D, a number of video editing and compositing programs as well. And they have done it on their own OS and Windows.
Windows updates sometimes break things too, but it has been nowhere near the idiocy I've seen with Apple.
As you say: [quote:1100ku2c] Apple are a multi-billion dollar corporation with thousands of engineers, and their software is broken
Given that, HTF is it possible to release software that constantly breaks things. Bugs are one thing, but this is on a completely different level. Do they recruit their software engineers directly from special ed classrooms? Seems to be.
So, no I blame them, not you, but if it were me, I would try to develop software with as few dependencies as possible. That I guess means standalone on Windows first, then browser versions. Wouldn't even bother with Apple version, let them use one of the browser versions.