I am glad Rich has put some more detail on his concerns for E-voting.
This is the silly season politically and passions run high.
My 2 cents on the Diebold (or any other electronic voting machine) is that they should just print out a easy to read and trackable (not to the voter of course) vote that is actually the one that is counted. Bar codes would be an easy mechanism with a corresponding reader to check your vote in the booth.
Easy to read for the voter and trackable to the machine. Bar codes in addition to the pictures and bold names and party affiliations. The reader in the booth would be to ensure that the bar codes match the printing. In any case you would still have a paper trail.
You could use a cross check by using the tallies to ensure matches and catch tampering.
Obviously a lot of other more sophisticated information data integrity and confidentiality mechanisms could also be used but I like to keep things simple.
As an office mate said yesterday. "Thank God 4 more days till shut up" :)