At Slactktivist, Fred Clark offers the best summary I've seen up to now of the theological implications of the discovery that Jesus had a wife--if such a discovery could be proven:
1. It would help to flesh out our understanding of the incarnation.
2. We would need to re-read stories of Jesus with fresh eyes.
3. Celibate priesthood would seem even sillier.
4. The unique place of Mary, the mother of Jesus, would change.
And then Fred concludes:
In other words, if it should ever be found, evidence that Jesus was married is more likely to inspire new myths to support the patriarchy than it is to dispell the old ones.
And I very much agree. This is one among several reasons I tend to be skeptical of the new "discovery" that Jesus was married. Though I can very much appreciate the critique of the anti-erotic and anti-incarnational strands of thought that entered Christian thinking from Greek culture in the formative period of the Christian church, at the same time, I tend to be drawn to the Barthian notion that the Word of God stands over against our comfortable, domesticated notions of who God is and what She intends in the world.
And for many of those who want to capitalize on the "discovery" that Jesus was married, this discovery is quite precisely about domesticating the incarnate Word of God and making that Word over in our image--to be precise, in a middle-class image that blesses what really ought not to be blessed in an unqualified and uncritical way, if we want to build a more humane world for everyone.