I could push a 0.7 update for F-13, but that would be the only newer version that does not require vala >= 0.9.5 (with the soname change).

Another option is to get gedit-valencia reviewed -- it's more light-weight and the current release works on the pre-soname-bump F-13 version of vala.

https://bugzilla.redhat.com/show_bug.cgi?id=518892

Can't be fixed, I'm afraid. We have vala 0.9.3 in F-12 and F-13. The first vtg
(gedit-vala) release that supports this is 0.8.0, but that would require an
update to gtksourceview2. We also cannot update to the 0.10.x series of vtg
because that depends on vala >= 0.9.5 and that introduces an soname bump that
would require other packages to be updated.

I recommend getting gedit-valencia reviewed and using that for F-12 and F-13
instead of gedit-vala:

https://bugzilla.redhat.com/show_bug.cgi?id=518892

I've tested several scenarios that crashes gedit-vala and valencia works fine
in those.