The thing that stands out for me, which no one else seems to have mentioned, is that the other man is physically holding Steve up/assisting him due to being weak.
Some have said the other man is "posing", which is ridiculous when he's quite clearly simply either looked in that direction as the photo was taken, or has clocked the photographer at the moment the photo was taken.
However, he's quite clearly helping Steve walk, yet no ones mentioned that.
I don't want to believe he's that badly ill, but remember WWDC and how weak and wobbly his voice was, it had never sounded that weak. He also looked off balance at times, and it's all very, very tragic.
I know it comes to us all, as others have reminded us on numerous occasions in this thread, but the Apple community is so unique in that we fell behind Steve and his vision for the future of the company, and as such we do feel a certain affinity for him.
I wish Steve all the very best, but it angers me how rapists, child molesters, murderers, and the like live until their old age with no serious illness yet innovative, great minded, good, decent people are struck down in their prime with evil illnesses like cancer.