ADS-B capabilties

[CO_Skymaster]

Does anyone know if ADS-B will eventually provide all traffic, or provide weather information like XM Weather? I was thinking of purchasing a Garmin 696, but you pay for the XM Weather hookup. I just don't do the type of flying where I need to pay that type of information on a monthly basis. If ADS-B will provide that service to pilots in the future at no cost, I also don't want to buy another GPS pad system.

Karl