It's certainly not good for Jobs that his health is declining, and may not be good for AAPL in the short term, but it gives Apple the opportunity to prove that Apple != Steve Jobs. If Apple can continue to kick ass for 6 months while he's gone, it indicates that Apple may do just fine once he's gone permanently.
Of course, 6 months may not be long enough to really tell. There's also the possibility that he really is dying and they're hiding it, or he simply plans to permanently retire, and they're just "easing" investors into the idea of an Apple without Steve Jobs. I hope neither is the case, especially the former.
Completely agree. The truly big test for Apple would really come 12-18 months after Steve's departure, when the product development pipeline matures. If they're able to keep the same "magic" with or without Steve, then it proves that he built Apple's success into their culture.
Historically that has not been the case though. In the short run it probably will not be much of an issue for Apple as there is not a huge shift in management.