In order to facilitate more discussion, I am reproducing here a comment I just left on Wade's post. It also ties in, to some degree, I believe, with the fruitful conversation we have been having here at Love Each Stone on the City church...
I agree that this is a key issue that underlies many of the discussions within the SBC. As such, this question lies at the root of many of the posts on my own blog.
I believe that biblical teaching on unity is at the level of the Universal Church (or the Body of Christ), the City church, and the local congregation (or New Testament "house church"), but never at the level of "denomination." An overstated emphasis on denominational unity and uniformity can also become an impediment to true biblical unity at the Universal Church, City church, and local congregation levels.
This is not to say that the SBC, in and of itself, is a bad thing, or has to necessarily be counter-productive in regards to biblical unity. It does mean, however, that the SBC should never be viewed as more than a tool, in the hands of local congregations, in unity with the various City churches, and the Body of Christ around the world, for effective work towards the fulfillment of the Great Commission. In order to be a more effective tool, agreement on doctrinal statements such as the BFM, can be helpful.
But whenever the SBC, in and of itself, is seen as representative of the Body of Christ as a whole, or as competing with our legitimate loyalty towards the entire Body of Christ, it becomes, in my opinion, not only a "denomination," but also a sect, and as such, contrary to the will of God for us as believers.