It's the testing, not the package building

It's the testing, not the package building

So, in RH world, it is really two current versions of Fedora and all Enterprise versions.

Well, OK. That's 5 distros for RedHat alone, same number as for the complete Windows world. For SuSE/Novell it's 9.0, 9.1, 9.2, 9.3, SLES8, SLES9. That's 11. Now for Debian/Mandrake/Ubuntu/Gentoo/Mepis/Whatever. You'll arrive at 20 at least.

Your argument about NT is correct, of course. But Software vendors that need to give guarantees need to be very confident about Red Hat's "certain guarantees" to rely on them with no testing on their own part. Look at SAP, for example. They are certainly not clueless wrt linux, and they make separate releases for errata kernels. I bet they have reasons to do so.

Please understand that I'm not arguing against Linux. I am just trying to explain why third party vendors have problems supporting the many different Linux flavors - because "supporting" means more than building an .rpm package.

Supporting Linux currently costs more resources for an ISV than supporting Windows. This is hard to dispute. To reduce the efforts, an ISV can decide to focus on a few very stable distros: RedHat and Novell enterprise probably, and Debian stable. That, however, would leave most of the community with their favorite distributions unsupported, and that's probably not what you and I want.

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