Hi,
just finished testing migration path from F19 to F20 for systems running oVirt.
F19 is going EOL one month after F21 release which is currently planned for December 2nd.
If you're running oVirt on Fedora 19 I suggest you to do it once finished to upgrade oVirt to 3.5.0.
I've saved some notes in the test request bug[1]:
Bug 1131828 - Test upgrade path from Fedora 19 with oVirt 3.5.z to Fedora 20
Enjoy!
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1131828