DREs really worry me because of security concerns and the fact that they cannot be properly audited. However, there is another problem with DREs, which this year, I think is going to be very serious.
News reports today are highlighting long lines at the polls for early voting. This is not unexpected, as the turnout for this election is bound to be tremendous. I'm very concerned about the impact a high turnout will have on an already stressed voting system. In Maryland, for example, we use touchscreen DRE machines. Precincts only have a handful of these machines, and they create a tight bottleneck in the voting process. As a poll worker, I've seen people take 30-45 minutes to vote. I've also seen it done in 5 minutes. The average, by my observation, is around 8 or 9 minutes. With an increased turnout, the expected growth in the lines is exponential. That is because the throughput of the election machinery does not change, so additional people will be added to the line much faster than the system's ability to absorb them, and the lines will be long - very long.
When Maryland switches to paper ballots with optical scanners in 2010, this problem will go away. The reason is that the time critical resource will be the scanner, and people can scan their ballots in seconds. The process of filling out the paper ballots can be massively parallelized. We could have 40 or 50 people filling out ballots at the same time, and even with only a couple of scanners, we can move people through the voting process much faster. Using touchscreen DREs, the time critical resource is the voting machine and voters spend on the order of 8 or 9 minutes, and sometimes much longer to vote. Paper ballots with op scan counting will eliminate long lines at the polls. And, I am worried that long lines are going to be a serious, serious problem in the election, which is two weeks from today. However bad it might be in early voting right now, and indications are that it's bad, I fear that on November 4, the problems will be worse.