While at T4G, one of the speakers quoted someone (I can't remember who) in saying, "God must love small churches since He made so many of them."
This statement was a good reminder for all of us. The lure of numerical church growth can be a pride-induced, dangerous one indeed. In our society, where bigger is almost always seen as better, it is easy to fall pray to the idea that larger churches are automatically better churches.
The real danger is that in order to become bigger churches, many end up compromising biblical truth - even the gospel itself. When the largest church in the USA is led by Joel Osteen, it is obvious that church growth for the sake of growth is a very significant problem.
It is interesting that the churches we see in the N.T. seem to have generally been small churches. Although it is difficult to know how large the church in Jerusalem was, we do see that they usually met in homes. Then as we read the epistles, all we see is meetings in homes. Therefore, there must be something positive about churches remaining relatively small in number.
The primary positive aspects to small church life seems to be community and accountability. You can only really know a small number of people and share life together. There is no way to do this with 500 people. In fact, it's difficult to do it with even 100. I suppose this is why people who attend large churches usually seem more excited about their "small groups" than they are about the church as a whole. In reality, it is the small group that is really their church.
Instead of encouraging large churches, let's encourage the growth of many smaller churches in order that we might follow the biblical model and be able to live in community with one another.