Different reason
Despite the 40£+ price difference NVidia is presently on its way to dominate the current Atom market. 3rd party Intel 945 GMA-driven Atom 330 (dual core) was being discounted to 39£ by some retailers in September and early October. They have now stopped the dumping in the inevitable run-up to Xmas, but it is bound to restart on boxing day.
If Intel does not deploy something by Xmas which destroys the basis for NVidia proposition they are looking at some misery ahead. They will definitely not be able to sell a lot of the crappy GMAs, surrounding chippery and thermally-half-baked MBs they forcefully bundle with the current Atom MBs.
Being under scrutiny because of the AMD Intel probably finds it difficult to use their usual method of golf-talking OEMs into "Don not use NVidia or...". So they actually have to "innovate". Hmmm... preparing 50-60£ to get a discounted NVidia from the post-Xmas sales may actually be a good idea...