In a letter to Apple employees released Monday morning, Steve Jobs informed his team that health issues have forced him to take a leave of absence from his day-to-day duties as CEO of the company. Tim Cook, who capably managed Apple (AAPL) in 2009 when Mr. Jobs had a lengthy medical absence, will again assume responsibility for day-to-day operations. Mr. Jobs will remain involved in “strategic decisions” for the company. No time frame was given for Mr. Jobs to return on a full time basis. This has revived a long running controversy regarding CEO succession at Apple. Read this article for more details.