Since rents went down after the dot com bust, why wouldn't they start to go up - inflation sure has. I've been in my current place for 4 years and no rent increase yet for me, and they dropped the price before I moved in. I'm sure they have been raising rates when units turned over, but that is normal practice if the vacancy rate is not high (again - that inflation thing).
As for availability -
Seems to be plenty of moderate-to-high end apartments and condos on the market at reasonable prices.
At the low end of the market it will stay tight until the Universities let out for the summer.