I have been on Google Plus for a week now and I really like it. There is so much more customization especially with the brilliantly simple idea of Circles, being able to group your audience into different sections and edit the posts and updates so that only certain people see certain things is a game changer.
I have not yet gotten into the Hangout (video chat) yet but in conjunction with the circles it certainly makes for an intriguing way to run a Tabletop style of RPG,
Imagine wanting to run a game of Dungeons and Dragons, the DM could create a circle for the players. He (or she) could then post updates for the game group that wouldn’t be seen by others. then on the designated game night simply start a video hangout just for that circle and the players could then join for the game. You could use public Google docs for the character sheets and maps, with the exception if dice rolls it would automate the entire game, if playing a Pathfinder or 3.5 edition game the rules are even available online as SRD.
Below is the inevitable Downfall video when Hitler is informed of the G+ rising popularity (some strong language):