Mormons

Here's a question:

On our excellent local community website, Virtual Lancaster, Mormons are listed under "Christian" on the religion page. The editor very helpfully made some other changes, but pointed out that Mormons describe themselves as Christian on their website. On what criteria could he exclude them, or treat them differently, given that they self-declare as Christian.

One option would be membership of ecumenical bodies, such as the World Council of Churches, Churches Together in Britain and Ireland, or Churches Together in England. However, that would also exclude a variety of independent fellowships not affiliated to those bodies who would certainly see themselves as Christian.

What would you do?