I have an iPhone, an Android phone, a Mac and a PC. I like the Mac over the PC (which is ten years old, so no wonder) and the Android over the iPhone. The bigger screen, and drag / drop files via my choice of bluetooth or wifi without using iTunes is pretty nice. iOS5 finally brought wireless sync, but it still has to run through iTunes, and isn't as slick as Android.
So, no... Android isn't destroying Android at all. It has seemed to inspire Apple to improve the iPhone slowly but surely, on the other hand.
My take on the status of things today is:
PC>Mac
Android>iPhone
iPad>other tablets
PCs with Win7 is more stable than OSX, and happen to cost a lot less on top of it. I'm still on Snow Leopard, but lots of people I know are bummed about buggy Lion.
iOS5 is about even with Android on complaints I've seen first hand, but Android phones are easier to deal with if you know how both systems work. If you're new to technology, then iPhones are probably more simple when you have battery. My Android lasts 3x longer with heavy use, and 5x longer if I just let both sit unused.
I have no tablets of any kind, but from what I can tell, Apple wins there so far.
Android will not be destroyed by Apple today, nor tomorrow. I think only something better than Android will destroy Android. Apple isn't it, yet... and at the rate they fix iOS, it won't be soon.