I imagine IP's are here to stay and actually, after seeing Holloween this year, I think that can be a good thing. I am up here this week, and for the past two nights, Holloween and the walking dead seem to be keeping the longest lines. I would prefer they dropped the walking dead and would not want to see it back again next year, but from talking to guest in the park, it does seem to still be bringing people in (not scientific, just chatting to folks we've met the last couple of nights).
I was surprised at how they made it the 'biggest' house. It just makes me wonder if they have any place for a ninth house for what I could tell, the extra length for the walking dead this year is from the sections done outside of the sound stage (you star outside, go in to the sound stage, then finish back outside).
I know you all are saying money wise it takes up as much as having two houses, but do they really have room for more houses anywhere?