As a long time Test Server player I just wanted to mention they have never done a character wipe. Right after Kunark came out they did an item wipe to punish the players for 'hiding' bugs from the devs. For a short period all the MOBs in SolB were dropping raid level gear. No one bothered to mention it to the devs. Since this radically skewed the level of gear on Test the devs opted for an item wipe.

The devs have since confirmed several times that characters on Test are 'safe'. As a side bonus Test is very friendly towards multi-boxers as a significant minority (if not a majority) of the population box.