After getting his diagnosis, I'm amazed he lasted as long as he did. He was a trail-blazer. Every single conservative radio show owes their existence to Rush Limbaugh, and up to his last day on the air he was still the best.
I had an inkling this was coming sooner rather than later, after I heard a show in January where he admitted that he was having to speak from the back of his throat instead of using his diaphragm. So I had my sad feelz then.
This will cause a massive shift in daytime radio from here forward. I don't know if anyone is capable of filling the hole he leaves.