Independent Survey?
Given the general theme of the comments in this thread, particularly the first comment from AlbertH and the AC who responded, it seems to me that no sensible mobile user trusts Ofcom, the Networks or RootMetrics for accurate stats.
Would The Register be able to step up and conduct their own research with other independent groups?
Granted, it's unlikely that such research would carry some weight with Ofcom, but a man can dream.
Colin