This is going to sound completely contrary to my "Design by Committee" post from a few weeks back, but I assure you that it's not.
Every once in a while I'm reminded of how much the 'end product' of a design project ends up being a collaboration. There are times when I get to work on a personal project and there is no client giving input, but most projects have an external 'client,' even if that is only one person making decisions for his/her organization.
I think that there is something very satisfying about knowing that a few very different people's ideas can be incorporated into something and not only WORK, but create a kind of synergy. It pushes you to reexamine your own process and open yourself up to an alternate way of thinking.
There's definitely a line where a committee waters down a passionate idea and where a few people can take a good concept and make it live and breathe. And it's nice to be on the right side of that line.