In the recent municipal elections in Finland, an experiment with electronic voting was made in three southern municipalities. In Grankulla (in Finnish, Kauniainen), Högfors (Karkkila) and Vichtis (Vihti) over half of the voters chose to vote electronically, instead of using the traditional paper ballots.
Out of the 12,000 voters, however, over 200 did not successfully finish their session with the voting machine by pressing OK twice. Most, apparently, did so only once, and thought that was the end of it.
200 out of 12,000 is not a very high percentage, but since there shouldn't be any problem at all in such a serious matter as an election, even this percentage is unacceptable. It was not a question of faulty machinery or an untransparent inaccountability of the manufacturers (as in the USA - see video on YouTube: http://korta.nu/05bf), but simply human error and lack of experience. But that is serious enough.
Before we go to electronic voting, there are apparently a whole lot of bugs to get rid of. Get out the Raid, someone!