You may vote from any one registered account you own on a Wikimedia wiki (you may only vote once, regardless of how many accounts you own). To qualify, this one account must:
not be blocked on more than one project; and
not be a bot; and
have made at least 300 edits before 15 April 2011 across Wikimedia wikis (edits on several wikis can be combined if your accounts are unified into a global account); and
have made at least 20 edits between 15 November 2010 and 15 May 2011.