The Mora thing might be a real concern but the registrations weren't "disappeared" (a word I associate with the Southern Cone, and find stereotypically used in conjunction with "Hispanics"). Might not. Can't find anything definitely showing why a contractor left off the party affiliation for 1k or so voters, which mattered in the primaries. And forced the voters to use provisional ballots.
http://www.abqjournal.com/news/state/apcaucus02-28-08.htmThe Florida numbers are a mess. I can't get through the clog of links referring to the Palast story to actually pin down a source. But it looks unofficial: "overwhelming" instead of "overwhelmingly", and "Black" instead of "black" looks like either a blog (not necessarily well sourced) or an issue-advocacy group with an interest in big numbers. Approx. 14k voters had their registrations rejected--mostly black--because they didn't check a box. I think a judge struck down that part of the law; if so this is merely out of date, if this is, indeed, what Palast is referring to. 85k (there's the number!) voters were moved off the active rolls (just in Lee county?) as part of routine voter roll maintenance (done pretty much everywher, else I'd still be eligible to vote in Baltimore, Newark, a few places in Eugene, a couple of precincts in Los Angeles, and in Rochester). They were kept as viable voters via provisional ballots, so that affects nobody, at least this year.
The Colorado 20% purge happened in 2004-06 and was also maintenance, for the most part (I suspect--since it's stale, it's not very urgent).
The Ohio and Nevada (
etc.) reference is milking the foreclosure nightmare in it's referring to the old--and new--requirement that you vote based upon your address. You amend your voter registration if you've moved. With a time-limit cut-off before the actual election. But it's true for anybody who's moved, for any reason.
http://www.dispatch.com/live/content/local_news/stories/2008/07/06/vacant.ART_ART_07-06-08_A1_5UAL914.html . However, this also tends to affect the young and the minority member more than middle/upper-class and whites, primarily because of home-ownership being (traditionally) more long-term stable, while apt. tenancy is usually shorter-term.