We have had a lot of emails about this. Some online stores in the UK are selling different mobile chips to the ones which we recently covered here.
There is a signifcant difference between the Mobile CPUs which 'Overclockers UK' and 'CPU-City' are selling. OcUK only appear to have the 1.65v based 'Desktop Replacement' CPUs in stock, and the 1.45v 'uber' CPUs are out of stock (We have had reports that they have 'never' been in stock. However, we have not had a reply from OcUK confirming or denying this at time of going to press.)
CPU-City are stocking the 1.45v CPUs - www.cpucity.co.uk. We have heard that the performance and 'overclockability' is huge between these 2 different voltages. Please be careful.
You need to be careful when selecting which CPU you are buying. AMD have information on the XP-M over on the AMD website.