Well, that's good news about Steve, at any rate. According to an Apple employee I met recently who knows Steve well, he really hates the press speculation and prying into anything that he considers part of his private life. Frankly, I don't blame him, though on the other hand he could have made it a whole lot easier on himself (and no doubt Apple's stock price) if he'd just given a brief explanation when the rumors first began circulating.
Assuming that the original surgery required removal of part of his pancreas, he could well be suffering from digestive issues and subsequent weight loss; the pancreas produces enzymes that aid in the digestion of protein, carbohydrates and fat. It also produces hormones that regulate blood sugar and stomach acid secretion.