"Listening to a British presenter, I realized that his sense of little and small were different. His general order of descending relative size went roughly in this sequence:
huge, big, small, little, tiny
while my American background views little and small as basically synonymous. Speaking with him after his wonderful talk confirmed his different sense of those two words."
Peter then asks, "is this a British vs. North American English usage difference?"
If you check the British ESL dictionaries, they typically define little as meaning small and the other way round. Similarly, the Concise Oxford defines little as "small in amount, size, or degree..." There is no mention of one being less big than the other.
There are, however, other differences. Least interesting among these is that small is only an adjective (the small of your back excepted), while little exists in two flavours: adjective & determiner. More interesting is that they are both marked, but little seems to be more marked. That is, when I want to know the size of something, it's typical that I would ask you how big something is, not how small it is. In this sense, big is unmarked. Yet, it is even less common to ask how little something is, about 10 times less common in the frame "how ~ is it?'.
Because of the problems parsers have distinguishing between adjectives and determiners, it's hard to get a good corpus view of all aspects of the difference, but here's a neat one: Search for (adj) + little in the spoken section of the BNC and you get the following (the first number is raw hits, the second number is hits per million words):
1 NICE LITTLE 161 15.58
2 TINY LITTLE 36 3.48
3 LOVELY LITTLE 35 3.39
4 POOR LITTLE 33 3.19
5 OTHER LITTLE 14 1.35
6 LITTLE LITTLE 13 1.26
7 SILLY LITTLE 13 1.26
8 CHEEKY LITTLE 11 1.06
9 PRETTY LITTLE 11 1.06
Try it again in the academic section and what do you get? Nothing. There are no such pairs.
Now do the same with small, this time with academic section first:
1 PROXIMAL SMALL 28 1.81
2 OTHER SMALL 20 1.30
3 DISTAL SMALL 6 0.39
4 NORMAL SMALL 6 0.39
5 UPPER SMALL 6 0.39
6 ENTIRE SMALL 4 0.26
7 INDIVIDUAL SMALL 4 0.26
8 NUMEROUS SMALL 4 0.26
And in conversation? Zip.
So it would seems that small is more academic, at least in this kind of pairing.
Now, this is stretching things quite a bit, but if we consider the general prejudice that conversation is trivial while academic language is weighty, long, and substantial, there may be an argument, if only a metaphorical one, for little being smaller than small. I think I'll put it to Lynneguist over at Separated by a Common Language.