Been around a while actually... for the most part I have been programming in N11 in many ARS tables for years, 311, 511, 611, 711, and 811 are also in use in many parts of the country.
Usage is generally assigned as follows:
2-1-1: community services, medical advice, United Way
3-1-1: municipal government services, non-emergency
4-1-1: directory assistance
5-1-1: traffic information or police non-emergency services
6-1-1: telephone company (telco) customer service and repair
7-1-1: TDD relay for the deaf
8-1-1: underground public utility location,[1] in Canada 8-1-1 is assigned for non-emergency health information and services
9-1-1: emergency services