Yeah, you might be a packager, but I bet you're not a rpm developer, now are you..?
The macros and compatibility between suse, fedora and mandriva as currently is and has historically been isn't worth shit.
The move to rpm5 is rather to standardize packaging around upstream, and not by trying to solve it with awkward macros to get half-assed adopted somewhere here and there, but never remotely sufficient to be of much relevance.
And just by stating that you're a package maintainer in opensuse doesn't really give you that much credibility to have insight on matters beyond suse packaging, much less rpm internals itself, and by claiming that macro sets in other modern distributions is rather compatible with yours, you're just revealing how way off you really are..
If you think more consistent macros is the solutions to everything, good for you, but what we want to achieve, and what I'm working on related to rpm5 is actually on implementing proper functionality within rpm itself, to be automized, externalized from spec files, and reduce the huge crap pile of macros and feeble attempts of achieving compatibility with %if foo blablbla %endif.
JPackage is a brilliant example of how miserably failures such attempts usually are, we'd rather work on making such project superfluous...
But go on, your macros will probably lead you to the magic leprecon, taking you to the gold at the end of the rainbow..
But in the real world, there's a need for cleaner, simpler, and well-designed means to achieve any sensible form of compatibility..
If you read our mailing lists, then you should also notice that Jeff's responses are well warranted, even though a bit hot-headed and misinterpreting people occationally, something which you cannot blame him for considering people's behaviour and attitude..
Jeff has been the person over the last month who's actually been the most active and helpful on cooker, and also given us a huge boost in discussing new ideas and related r&d, while being frequently trashed by the same group of people with their own agenda.
You can find these same people having been especially active dating back to september since the mageia announcement, trolling and generally generating tension on the list before Jeff turned up as well..