If part of the team is remote, then the entire team is remote. Keep this in mind for meetings. If anyone in the meeting is phoning in, then it's best to just keep everyone at their desk and have everyone phone in as if they are remote. Otherwise, the in-house folks just end up tuning out the remote employees and you end up with two meetings. A meeting of the in-house and a meeting of the remotes.
Team bonding is always an issue. Fly people in once or twice a year and really schedule most of their time in-house to be situated around social activities. We do daily stand ups and block out thirty minutes. Wrap up stand up in five minutes, spend the other twenty-five bullshitting about what's going on in your life. When you're not in the office, it can be difficult to really know what's going on in people's lives. If someone has a sick kid, or a grandparent in hospice this isn't going to be readily communicated unless you schedule and encourage some non-work-related conversations.