The Garmin 1000 suite is part of it, but does not have all the NEXTGEN capabilities yet. ADS-B, RNP, and CPDLC would all be an add-on "boxes" that could possibly interface with it in the future.

TIS is not ADS-B but works similar to it. TIS information is delayed (not real time). ADS-B IN traffic info will be appx 1 second "old"

Think of it this way-
Your current 4096 code Mode-C Transponder will Eventually be a "backup device" to ADS-B.