I belong to two writing groups, one local and one virtual.
My local group meets once a month at a Panera Bread near my house. We exchange 15 or so pages of our works in progress a week ahead of time and then come to the meeting with questions and comments. It usually takes about 3 hours to get through everyone's pages, then we chat a bit about industry news, who's querying, who's agented, what books were great or not-so-great. I've been going since July and it's been great to connect with some locals who all have the same goal: to be published writer's of children's fiction.
My online group is similar yet different. For one thing we have a name: The Interrobangs. We have a Google Group. We also do a regular swapping and critiquing of manuscripts. But because we're completely virtual (I haven't met any of the others in person) we're pretty active with regular emails and Twittering (I refuse to write tweeting). We talk alot about things we see online, blog posts, deal announcements, and so it seemed natural that the next step was a blog.
I'm really proud of our first post, about the whitewashing of the cover of a highly anticipated YA sci fi release. It's a topic that, unfortunately, comes up again and again in the YA publishing world.