I'm very glad to see the AOLserver community becoming more organized. (Special thanks to Scott of course.) I'd also like to encourage everyone to come to the AOLserver chats we have every Thursday - we regularly discuss these issues.
I think non-Win32 OpenACS ought to run on a stock AOLserver distribution. Other than possible internationalization issues, I don't think there are any changes Arsdigita made that would affect performance. Most of the changes were bugfixes or new modules that should be fine in 4.0. Which reminds me - I think we should ask Scott to import the nssha1 module too.
Regarding the Windows version of 4.0, I'm happy to keep the code separate for now. Once 4.0 is released, I can make a full set of patches and we can properly discuss whether the Windows code should be folded into the core. (I might actually lean towards "no" myself.) I *would* like to see Windows changes to the modules merged back in, as very few changes are usually needed. I'd respect the desires of each module's admin on that issue however. I'm willing to work with Win32 core changes as a "module" on SourceForge if that is what the community prefers.
I'm also hoping to revive Yon's AOLserver test suite framework, which is currently Windows only. It would be especially useful for modules which I don't personally use but would like to compile and include in my distribution.