If Jobs is still around then, he'll have relinquished the CEO title to someone who can spend full time on the job. He may still have a role as "visionary" (even Woz is that today), and advise on strategy - but Apple needs a full time CEO.
(And don't count on Tim Cook continuing in the "acting CEO" role forever - Tim's doing the work, and Jobs is still getting credit. Not a good career path for a senior exec.)