Current usage
The comparative less is used with both count and uncount nouns in most informal discourse environments and in most dialects of English, and in these environments, the word fewer is hardly used at all. Many supermarket checkout line signs, for instance, will read "10 items or less"; others, however, will use fewer in an attempt to conform to the prescription. A British supermarket chain replaced its "10 items or less" notices at checkouts with "up to 10 items" to avoid the issue. It has also been noted that it is less common to favour "At fewest ten items" over "At least ten items" – a potential inconsistency in the "rule", and a study of online usage seems to suggest that the distinction may, in fact, be semantic rather than grammatical. Likewise, it would be very unusual to hear the unidiomatic "I have seen that film at fewest ten times
http://en.wikipedia.org/wiki/Fewer_vs._less