What area of SD are you looking in? I am looking for 4-5BR in Carmel Valley.
I could see a short term upward pressure on rents as foreclosed houses stand vacant and are not offered for rent.
Longer term, though, as local recession eats in to affordability, rents will decline as demand decreases due to falling employment. If nothing else, reduced construction jobs pull down the local economy. Reduced demand means reduced willingness to pay rents.
As the local economy contracts there ends up being a net exodus. This does not mean that people everywhere are packing up their bags; rather, people naturally leaving are replaced a little less vigorously. Decreased population applies significant downward pressure on rents.