This leaves only two possibilities: that there was widespread ballot-stuffing or that the results in some or all areas don't reflect any physical count of the ballots but were fabricated whole hog on a spreadsheet.
Between the obviously rigged election and the creation of a martyr for the opposition, the Iranian people have had enough. Mousavi is encouraging his suporters to stand up to the regime, and they are. The Basij militia are acting like thugs and vandals--breaking windows, destroying property, and beating helpless grandmothers (acording to some reports). All this is only inflaming the ire of a people who are increasingly seeing the current Iranian leadership as illegitimate. It's only a matter of time before key elements in the government and/or petroleum industry side with the protesters and refuse to continue supporting the cabal. That will be the death knell of the dictatorship.
There are scores of videos pouring out of Iran as I write this. I've watched many of them, but the one I have embedded below in some senses is the most amazing. I couldn't help but cheer (out loud) on the protesters as I watched it. Can you watch this and not cheer them on too?
note: A great site for updates is Andrew Sullivan.