Q: Will there be guild support?
Guilds and clans in Diablo II were often organized using chat bots and out-of-game online communities. Hope had arisen that this would mean the developers saw this need as enough to implement guild support in Diablo III, but the idea was shot down. They will not have guild functionality available for release, but something may be implemented after release. They saw a lot of guild ideas that didn't get implemented in Diablo II as great mechanics that they want to work on in the future, but they want to make sure that if they do implement guild functionality, they will do it right.
They said exactly the same for diablo 2 and the possibility of guild halls etc. So don't get your hopes up... More likely than not, we'll never get guilds in diablo 3.