The WHATWG Forums
Let me introduce you to The WHATWG Forums! If you don't feel comfortable with mailing lists but still want to discuss the future of HTML, how to use HTML5, or ask for help, then these forums are for you.
More forums or sub-forums will be added as needed. Contact me (zcorpan) for administrative stuff (becoming moderator, etc).
I think a forum is more comfortable for a discussion than a normal blog. Hopefully it will be used in the future…