trakkerguy - 7:19 am on Jan 10, 2012 (gmt 0)
No, a 301 is not really "permanent".
I have removed 301s and put the old sites back in place, and they have often returned to previous ranking.
Its not quick usually. It depends how long the site was redirected, among other things. But they have come back for all the dozen of so I have experienced.