Once upon a time we used IRC to communicate, but we've moved to something more modern: Slack. Slack has quickly become one of the most popular communication tools for startups and mid-size businesses. It's a lot like IRC, but it has first-class web and mobile clients, which makes it much easier to access in our modern mobile-device world. There's also an IRC gateway to it if you can't give up your favorite IRC client (but beware that you'll be losing some features like images and file sharing).
We'll send you an invitation, which you'll use to set up your account. Once that's done, just open up reviewboard.slack.com in a browser or one of the apps (there are mobile apps, and a fairly nice Mac app). You'll be expected to be present in the #students channel at a minimum, and there are a few others you can join if you're interested.
We expect you to maintain an active presence in Slack. Slack keeps logs of recent activity, so you don't need to be connected all of the time (though you certainly can be). You should make sure you open things up at least once a day, and we highly recommend turning on push notifications for your mobile device. This is so that we or your fellow students can ask you questions and get an answer from you, and vice-versa. Ideally, check in on Slack as often as you're checking Facebook.
You'll probably need to communicate frequently with the other members of your team, and Slack is the right place to do that.
After the sprint, we'll set up a time for a weekly meeting which will happen using some kind of video chat technology. Unless you have a very good excuse, please try to make it to every meeting. Weeks when we ask for a demo video we'll have optional "office hours" instead of a required meeting.
Some communication also happens over mailing lists. As we stated earlier, you might want to join the reviewboard and reviewboard-dev mailing lists.
Each week (except on weeks with Demo Days), we will be having a short video meeting where the point person for each team will give a short update about how each of the projects is going. We'll also ask each of you to talk very briefly about what you've learned in the past week. Slides or other formal presentation matter are not necessary, and these will not be recorded. We just want you to share the lessons you're gaining with the other students, and it also gives you an opportunity to touch base each week. These meetings should last an hour or less.