I'm an investor and look at property all over the area. And it is true, DOM is a local measurement. Ask the agent to see the Market Conditions Report for your property, it will show the median comparable listing days on market. This will be for comparable properties near you.
I am sorry - I have to agree with Anna - this is too loaded and unspecific of a question. Some properties are relisted with different brokers, put into another catagory and is misleading on the DOM. I have an area of Germantown I sell in, that for the last 2 years have never had a listing last more than 4 days, while there has been listings in other areas that have had "fall out" due to fianancing concerns.