This is more a general question for all forums really, but I'm curious to hear from any admins who have any experience in this. I've signed up to several forums through Google, one or two with Steam and it's simply a clicking exercise. You're in that much quicker without the sometimes tedious registration process. It does strike me as an attractive option for my forum, but I wondered what the pitfalls were and of course the major advantages. WoltLab Suite has this option built-in, so it's easy to set up.