reason,
The additional residents in Irvine will be accommodated by additional construction by the Irvine Companies and the builders to whom they sell land. This influx of people will not create a shortage of supply which might put upward pressure on prices.
The financial markets always want the FED to lower interest rates. Lower interest rates are great for stock and bond markets. Recent activity in the bond markets -- they have been selling off -- are indicating an increase in interest rates. Investors are demanding higher returns to compensate them for increased inflation. In that kind of market environment, the FED will probably not be willing or able to lower interest rates, but even if they did, it will not cause a drop in mortgage interest rates.
The article in this link: <a href="http://www.pimco.com/LeftNav/Featured+Market+Commentary/IO/2007/IO+July+2007.htm?ref=patrick.net"><strong>Looking for Contagion in All the Wrong Places</strong></a>, is a bit long, but if you read it, you will gain a better understanding about the relationship between mortgage interest rates and the FED funds rate. Basically, the difference between these two rates -- called the spread -- is based on the market's perception of risk. If people are not defaulting on mortgages, the spread will be low, and mortgage interest rates will be very near the FED funds rate (which has been the case for the last 5 years); however, if people begin defaulting in large numbers (as is the case today) investors start demanding compensation for the increased risk, and the spread will increase. So if the spread increases from its current 1.5% to its historic average closer to 3% or 4%, mortgage interest rates will rise. So even if the FED lowers the FED funds rate, the increase in risk premium will drive up mortgage interest rates.
I know that answer is rather long, but I see mortgage interest rates as increasing over the next several years, and this will make the price decline in Irvine even worse. Mortgage interest rates declined 30% in the early 90's which did soften the drop. Interest rates dropped then (in spite of large numbers of foreclosures) because they were well above their historic norms in 1990. This time, the opposite is likely to happen because interest rates are well below historic norms.