Don't underestimate how many people go to live shows because of the rain, sweltering heat, and the air conditioning -- that describes 90 percent of DHS days...
It won't last much longer than the show, which will probably stick around for more seasons than many people think. Despite the fact that it's losing viewers, it still has more than its competition (Even though The Voice is probably going to beat it within the next year). I'd say the show could get 3 more seasons out. The ride will only last 2 years, so it'll be gone by 2019.
I fear it will be around for at least a few more years. I wish they would close it already and put a new original attraction there. I liked AI E when it opened, but I feel like it has out lived it's popularity, but I have no idea how many folks actually still visit the attraction. Of course my opinion could be tainted by the fact that I am definitely over AI this year, in fact this will be the first year that I don't watch. I'm ready to move on and I wish Disney was too!