I have been browsing the Forums a little and was looking for some metrics to evaluate and even (to some extent) attempt to predict how a real estate market is doing on a general basis. Here are some metrics I cam up with: (Also, I would love if you guys could extend this list or tell me what metrics should be removed) Here we go...

Housing inventory available in the market (These rates can give you an idea what is currently happening in the market. It is in direct relation to the demand and supply ratio). 

New builds will also give you an indication on whether developers think the markets will perform in the near future or not.

The Credit Markets (How much credit or money is available in the market to be given to borrowers)

Interest rates (These rates will directly influence how willing and able borrowers are to borrow money) 

Disposable Income (Obviously the more disposable income people have the more purchasing power they will have as well. ---See how incomes in relation to CPI or cost of living have changed). 

To give you an indication of what is happening in the future one can have a look at how the REBAR futures are performing.

Inflation rates: If there is high inflation people want to get rid of cash and buy assets. One way to do this is to purchase real estate in order to hedge against a devaluation of the currency. (as long as the returns on real estate are higher than inflation that is).

Then there are social and demographic changes. Think about this, demand is only created if there are people. The less people there are, the smaller the demand, thus decreasing the size of a given market, this includes real estate.