Fast compared to what? The last time I checked (~1 week ago) Cortona had six homes available -- 4 from the latest phase and 2 from the previous phase. The models were deserted. LR models around the same time were teeming with people.
109 Lattice (Olivos Plan 2, I believe) closed for $935K on 4/30. It was a short sale, but still I would have a hard time justifying paying $1M+ for the smaller, next door neighbor.
http://www.redfin.com/CA/Irvine/109-Lattice-92603/home/5902672
I will be hesitant to categorize any part of Irvine as amazing. The only exceptions I can think of are parts of Turtle Rock and Turtle Ridge.
QH is not bad for Irvine in my opinion -- I just wish the asking prices for the SFRs here were more realistic.
I was at Cortona this past weekend and was told that the Cortona Plan 1 will almost certainly see a price increase of ~$5K in the next phase. If I remember correctly they had a plan 1 and a plan 2 available from the previous phase release.
BTW I always thought LA was way overpriced but compared...