In my opinion, small groups in the church do not work if they exist simply for social reasons. They've got to have a focus that brings them together.
Even if it's just a group of veterans that get together to play spades and end the hour with a bible study, it is amazing how the focus need + Christian devotion binds them together.
As you can see, I reject the author's viewpoint.
I had one young, exhuberant disciple that I sponsored as student pastor of a church in Cincy, say, "What about a Pub Group, Chaplain?"
I wanted to answer as a prohibitionist, traditional Methodist, but then I thought: "Jesus probably would've visited the pubs of the publicans."
I have to say, I agreed with most of what the author of this article had to say. The only two disagreements I have are his disparaging usage of the term 'pietist' (I look at Methodism and the Holiness Movement as essentially pietistic, but at the same time, they are by and large still what he terms 'confessionally orthodox' with regard to the usage of liturgy and the arrangement of the worship service), and his bad-mouthing of small groups. Where they interfere with corporate worship, as Corin said, they are a problem, but the Biblical concept of fellowshipping with believers is carried out most emphatically in small groups of believers.