The optical scanner systems were actually used in about 42 of the 67 counties in Florida. Unfortunately the punch card or Votomatic system was used in the remaining 25 counties. These systems are already seeing some limited usage. They were actually used nationwide in the most recent Brazil elections. This type of system could provide near perfect voting if done correctly, with a good visual layout, multi-language selection, multilingual audio back up and the quick feedback to confirm the choice with the ability to easily change the selection before making it official.
Tabulation can also be near perfect as it involves no machinery purely a digital transaction.
Obviously, digital has problems too. A virus and hacker-proof system that also has good backup systems would have to be there to build confidence with the public and ensure accuracy. The biggest psychological hurdle would be the lack of a physical ballot trail. Technology is needed but it is not a panacea. We can use the latest hardware and software and still produce ballots as confusing as VCR programming today.