Vodafone has replied to the adjudication by the Advertising Standards Authority saying that the ruling does not actually question "the factual validity of Vodafone’s ‘fastest and most reliable’ mobile broadband advertising claim [....] nor does it challenge the validity of the LCC results".
The study carried out by LLC, the world’s largest independent wireless engineering company, lasted two months and found out that Vodafone was indeed quicker than its competitors between March and May 2008 (at least for these tests).
However, what the ASA is recommending is that these claims should be backed by further research (and tests) in order to support Vodafone's marketing claim that it is the "fastest, most reliable mobile broadband in the galaxy..."
Which Vodafone has agreed to. This means that the company will almost certainly come back with either a more complete set of data or, for sake of clarity, perform another, more extensive test.
Vodafone also provided with some interesting stats which showed that the Vodafone's speed during the test reached 1.2mbps, which is roughly one sixth of the maximum theoretical (and advertised) speed of 7.2mbps.