>> The biggest one I can think of currently is that rubygems *doesn't
>> support* gems that are targeted at specific runtimes. =A0For example you
>> cannot specify that gem "x" applies only to ruby 1.9 and greater.
>
> that is not true, see required_ruby_version.

Well, not *entirely* true, apparently.

>> This also causes odd failures when using 1.9 on windows, because if
>> you do a "gem install win32api" it ends up installing a gem that has
>> binaries compiled only compatible with 1.8, so it fails at runtime.
>
> I believe those are separate things, those issues can be solved with
> fat-binary gems or compiler been available for Windows users.

To me it feels like more of a work around than a solution.  Plus I'm
not sure that fat-binary gems would be an ideal way to distribute std
libs.

-r