People seem to confuse the rate of acceleration with speed. If you are traveling in your car in a forward direction where you are accelerating to get onto the highway your speed is increasing. Once you get to the merge point you match your speed with other cars by reducing the acceleration. This means you continue to raise your speed but do so less quickly. When there is a good match you merge into traffic.
If house prices are rising but they are doing so less quickly in years past we still end up with higher prices. Only if prices are falling in an absolute sense will the value of houses be in decline.
Headlines reported in many news reports are there to catch your attention. They are not to produce a balanced view of the market reality.
There is a report from the Office of Federal Housing Enterprise Oversight (OFHEO) which shows what has been taking place in the prior 3 month reporting period. Take a look as you can find your state and likely your city if you are in a MSR. It will given you an idea of what is going on with prices/values as opposed to the rate of increase or the rate of new construction sales.
John Strozier provides a summary of the report on his blog.