Well I'll give you this much. If Diebold is using ANY commonly used database whether it be Access, MS-SQL, Oracle etc., and worse yet if they are using a non-proprietary operating system then YES they are vunerable to problems big time.
I personally haven't looked into Diebold but I assume that they are using their own in-house-written operating system. If they are not, then they are foolish.
Ohio does not use Diebold machines.
End of argument.
Nope, they're using Microsoft Windows.
Check out the video at the first link on this page, which is a link to instructions on how to download the 160Mb BitTorrent-hosted video that demonstrates the exploitation of the Diebold software:
http://www.equalccw.com/voteprar.html
There's also a few screenshot-by-screenshot demos linked there too, plus interesting exceprts from the Diebold policy guides.