Short version: When Steve Jobs went on leave of absence before Macworld, Apple said he would return end of June. Wall Street Journal, citing people familiar with the matter, say Jobs will indeed return.
Longer version: After suffering a protein-digestion problem which rendered Steve Jobs unable to function on a day-to-day basis at Apple, he took time off and corrective measures. Periodic visits back to the HQ not withstanding, and speculation of a surprise cameo at WWDC running ever-rampant, Jobs is still on track to return just precisely when Apple first said he would.
New iPhone good to go: