System and method for realtime community information exchange

1. A system for a traffic mapping service, the system comprising:

a server configured to:

wirelessly communicate with a plurality of navigation devices ascribed each to one of a plurality of members of the service, respectively;

receive information on a momentary location of each of said members from said plurality of navigation devices;

provide a traffic data on a map based on the momentary locations of each of said members from said plurality of navigation devices;

receive an user traffic notification from a particular member of the plurality of members of the service, wherein the particular member is traveling towards a destination location;

select a subset of navigation devices from the plurality of navigation devices based upon a direction in which each of the respective members of the subset is traveling relative to the destination location such that at least one of the plurality of navigation devices traveling in a direction away from the destination is excluded from the subset of navigation devices; and

update the traffic data on the map displayed to the subset of navigation devices to include the user traffic notification.

2. A system according to claim 1 , wherein said server is further configured to provide a preferred route to the particular member to arrive at the destination location, based on the momentary locations of each of said members from said plurality of navigation devices.

3. The system of claim 2 , wherein the server is further configured to select the subset of navigation devices based on a particular road specified by the particular member, wherein the particular road is included in the preferred route.

4. The system of claim 2 , wherein the server is further configured to select the subset of navigation devices based on a particular road specified by the particular member, wherein the particular road is excluded from in the preferred route.

5. A system according to claim 1 , wherein said server is further configured to receive from the particular member the destination location.

6. A system according to claim 1 , wherein said server is further configured to estimate destination location based on historical tracks of the particular member.

7. A system according to claim 1 , wherein the server is further configured to select the subset of navigation devices such that each of the subset of navigation devices meets a set of group definitions defined by the particular member.

8. A system according to claim 7 , wherein the set of group definitions includes: a type of transportation, a direction of travel, a distance from the particular member, and a type of road being traveled.

9. A system according to claim 1 , wherein said server is configured to re-calculate the subset of navigation devices periodically.

10. A system according to claim 9 , wherein said server is configured to re-calculate the subset of navigation devices periodically according to a list comprising changes in characteristics of the subset of navigation devices.

11. A system according to claim 1 , wherein said server is further configured to calculates velocities of the plurality of members based on changes in the locations of the members between one update of the traffic data on the map to a next update.

12. The system of claim 1 , wherein the server is further configured to select the subset of navigation devices based on a type of transportation for each of the plurality of navigation devices.

13. The system of claim 12 , wherein the server is further configured to select the subset of navigation devices such that each navigation device of the subset of navigation devices corresponds to a similar type of transportation.

14. The system of claim 12 , wherein the server is further configured to select the subset of navigation devices such that the subset of navigation devices are within a certain distance of a momentary location of the particular member.

15. The system of claim 12 , wherein the server is further configured to select the subset of navigation devices based on a type of roadway preferred by the particular member.

16. A method for providing updated traffic data to members of a traffic mapping service, the method comprising:

wirelessly communicating, by a server, of with a plurality of navigation devices ascribed each to one of a plurality of members of the service, respectively;

receiving, by the server, information on a momentary location of each of said members from said plurality of navigation devices;

providing, by the server, a traffic data on a map based on the momentary locations of each of said members from said plurality of navigation devices;

receiving, by the server, an user traffic notification from a particular member of the plurality of members of the service, wherein the particular member is traveling towards a destination location;

selecting, by the server, a subset of navigation devices from the plurality of navigation devices based upon a direction in which each of the respective members of the subset is traveling relative to the destination location such that at least one of the plurality of navigation devices traveling in a direction away from the destination is excluded from the subset of navigation devices; and

updating, by the server, the traffic data on the map displayed to the subset of navigation devices to include the user traffic notification.

17. The method of claim 16 , wherein selecting the subset of navigation devices is further based on a type of transportation for each of the plurality of navigation devices.

18. The method of claim 17 , wherein the subset of navigation devices are selected such that the subset of navigation devices are within a certain distance of a momentary location of the particular member.

19. The system of claim 16 , wherein selecting the subset of navigation devices is further based on a type of roadway preferred by the particular member.