They make new stuff work with other people's old stuff.
I have a
Sony Dream Machine stereo system w/iPod dock that I got back in 2008 for christmas. Now at the time, I had a 3rd generation iPod Nano 4GB (which recently got stolen) and it was perfectly compatible with the stereo because it came out about six months before the Dream Machine did.
After I bought the brand new 6th Gen iPod Nano in 16GB, I was expecting the radio to not recognize the iPod and possibly not even work with it's interface. I was wrong.
As soon as I plugged it in, the iPod suddenly popped up with a Sony logo at the top, and the radio worked 100% with the new iPod. Keep in mind that the radio was released two years before the new Nano came out.
If a company like Samsung or maybe Sony had a system similar to this, when you plugged in one of their portable music players it would probably be like "what the forget is this, I can't operate with it whatever it is".
Apple are smart for this reason. Discuss.