Nokia knows very well when it plans to ship the N900 to India (for example). It doesn't have to figure out exactly when the product will make to every retailer in India but it does know when it will be generally available - that date is a function of when it plans to start shipping to that market and the normal length of supply chain to hit retail. They could easily say "Available in India from January 15th 2010" and then people can go ask their local retailer when they're getting it.