Where church is a living organism, it follows that structures serve but do not define the body of Christ. Cell groups serve community, but do not define it. The same with Sunday services. Community is wherever people come together in a way that recognises Jesus Christ, and what He stands for.
Yesterday, there was an improptu Cell Group in my office base, when four of us gathered and then shared in Bible Study, spoke of our struggles to walk in righteousness and continued in prayer. Today, there was the Sunday School picnic by the beach, where there was fellowship, food, fun and real conversations. And in each of these, we are developing community as the body of Christ on earth.