People being hacked since the last Server Check.

Some may not have seen this:
http://venturebeat.com/2011/11/23/online...exclusive/

It [Nexon] said that in April 2011, a server in North America was hacked and that may have led to access to encrypted data on 24 million accounts. Nexon found that virtual currency had been tampered with and it suspended the accounts of users who saw abnormal increases in virtual currency.

This could explain some of the earlier hackings of those with weak passwords who have never changed them since before April.