When it comes down to making decisions and leading your team, you might decide to have one of two main approaches:
1. Open Team
2. Organized Hierarchy
In an open team, members of the team vote and/or consent on features, ideas, and more, with the creative vision of the game shared between all members. You are more of a mediator/moderator than a leader, and your main task is keeping things together. The team functions together as a 'board' to make decisions- even if only within departments. This style is very good for small projects, but requires all team members to be active and converse regularly. Often times, I will see something like this in developing a Flash game, where the Programmer and Artist are mutually equally bound to the creation of the game, and closely share ideas and bounce things back and forth in a full collaboration. The open, informal attitude of this is really great for small groups of 2-4 people, but impractical when large productions are going on.
In an organized hierarchy, you (the creator/project manager) have the absolute say over how the game will be designed. Of course members can give input, but you personally decide what to add, who does what, and more. This style obviously requires a more active role in leadership and a lot of sustained 'charisma' to keep things going on your part.
Most people tend to gravitate either to a middle ground or an open team style. However, there are 'control freaks' out there who enjoy making sure things match their artistic vision. For them, a more organized approach may be taken, with departments and so on. This is not necessarily a bad thing, but it means finding teammates willing to follow these restrictions may be harder.
Seven Strategies for Being a Sucessful Leader
Some good points to follow:
1. Lead by example... if you need things done, be proactive and work hard on your part of the pie. When others see how much you are working, they too will pull harder.
2. The arts take time... don't try to rush people unless it's absolutely necessary. However, giving too open deadlines may lead to procrastination, even when completely unintentional and from those who normally don't procrastinate.
3. Contact team members regularly- at least once or twice a week and talk with them, even if it's only partially related to the game. Be sure to spend some conversational time not focused on the game, but instead on just conversing about whatever.
4. Be friendly and courteous. Don't yell at people or accuse them of not doing their part, even if you are planning to remove them.
5. Make your intent clear, and if you aren't sure about something, say, a design, or an art direction, talk with team members or 3rd party 'contractors' about options, or go on a little web search yourself.
6. Show interest in the works of your teammates, both for the game and otherwise. Not only does this keep morale up, but it can lead to future opportunities.
7. ALWAYS be constructive when critiquing an asset for the game. First note something you really like, then SUGGEST a change that could improve it towards what you are looking for. Try to be as specific or even draw/find an example.