Hi,
We can alway have a ruby package and a ruby18 package at a later date, much like what will happen when I make python3 to python. Currently, it seems that nothing in the repos builds against ruby-1.9 so I (or whoever takes ruby over) can wait for that transition and provide a ruby19 package.
Well maintaining both versions (at least for some time) would be an ideal solution, only I didn't dare to suggest it because I can imagine it takes quite some work. :-)
Ondřej -- Cheers, Ondřej Kučera