Let me say this forcefully. Linux is not Redhat. Redhat packages Linux, as do others. They support it as do others. They contribute to it, as do others.
They don’t “define” it. Thats what standards bodies are for. LSB.
I keep running into all sorts of problems in getting things properly working with hardware or software that has been built around the Redhat == Linux model. Sadly, this does nothing to convince me to use more Redhat.

Every decision has a cost or consequence. Lets talk for a moment about the cost of switching to Redhat. Hey, we get ancient kernels with poor to non-existent support for new hardware coming out, no support for large file systems, or reasonable file systems (ext3 is not reasonable as a file system for >16TB volumes). Things like wireless don’t/won’t work without serious kernel brain surgery (the backporting is already bad enough IMO).
Of course their rationale is that they need to support their product, and guarantee stability. Fine. Good points. Why should we use this product when it cannot do what we want? Shouldn’t we be free to select another? Yes of course we are. They will tell us that.
Of course the issue is when the ISV hardwires (conciously or otherwise) their application to a particular distribution. This means it is a struggle at best to get it to run.
Note that this is not Linux specific. Windows is as much not windows. Lets ask all those x64 Microsoft office users out there how well things work. Or the Wince users. The point is that this is a problem across OSes as well as within single OSes.
It is in my opinion, a *seriously* bad thing&tm; when ISVs write to a particular distribution of Linux (or windows for that matter), and *not* as they should, to a particular LSB or standards level. Standards are there for a very good reason. This way, if Redhat does something we don’t like, we can move our code elsewhere easily. Linux had been Linux up to about a year ago, and then someone started thinking “hmmm…. differentiation, breaking compatibility… goooooood”. No. That is *not* good. It fractures the base, and does not drive customers to you. It drives them away from you.
Dumb decisions often have serious consequences unless you get real lucky. Its time to push standards hard. No more “Linux == Redhat”, we do all users a disservice when this happens.