Apple on Monday admitted that a serious bug in Snow Leopard could cause permanent data loss and said that it is working to find a fix for the problem. The company, responding to a growing number of posts on its discussions forums, confirmed that users can loose data when logging into the guest account on their Mac first and then logging into their regular account. Although the problem is not widespread, the consequences -- especially for those without backups -- could be disastrous: some users are finding all their data to be missing and th