Be prepared to make up deficiencies in their skills, if needs be by doing additional work behind the scenes, not in place of their contribution to the team. Honesty counts a great deal in teamwork. If you say you're going to do something and don't deliver because you were sick, then someone finds you were really at the gym, you will lose credibility within the team, and this is bad form. In a properly organized team everyone is reliant upon every other member, not just one or two. Not everyone's skills are the same.
Some people are more competent at one task than another.
When it comes to deciding who does what, it's a good idea to find out exactly who can do what first. By the same token, just because one person can 'build hardware' doesn't necessarily make it the task for them. It may be in their individual interests to do some of the management aspects while last weeks manager is this week's technical guru. Determining the needs of individual team members early on is an important aspect of team success. Working out who will lead a team is just as important an issue.