Taken from Wikipedia http://en.wikipedia.org/wiki/Street_date
"In business, a street date is the date a particular product is to be released for sale to the general public.
Typically, retailers receive shipments of stock prior to its street date release, so that the product can be placed on display shelves for store opening that day. Shipments come marked very clearly with a "do not sell before release date" label designating a street date mandated by the distributor. Shipments may sometimes arrive up to three weeks in advance.
Retail outlets can be severely punished by manufacturers for releasing a product even a day before the street date. If a retailer breaches the contract establishing a street date, the manufacturer may impose fines, may withdraw privileges to distribute future products from that manufacturer, and may file a lawsuit to enforce the contract. However, there is no documentation of a retail chain or store being fined or any action taken against them."