I notice that the interesting but (to me) irritating word 'poo' (noun) is now being used on the 'dog fouling' thread. I have consulted the Oxford English Dictionary (latest edition, I believe) which doesn't recognize it as a noun but which records the verb 'to pooh' - first citation 1980 (from The Times - 'bees pooing on cars'). When I was a boy, 'poo(h)' meant 'smell' - 'Crikey, what a horrible pooh!' - and never s**t. (Will I be allowed to use that word? - ah, no, I see).
What irritates me is the use of the word by adults talking amongst themselves, given that it's basically a nursery word ('slang, originally children's' says the OED 'pooh' entry). I would myself like us to be able to use all four letter words in their original sense - specifically 's**t', 'f***' and 'c**t.' But, given that that's a pipe dream, can't we find a more grown up word that 'dog poo'? 'Dog dirt' is what I was brought up to say. There's also 'dog mess', 'dog droppings' 'dog excrement', 'dog muck', 'dog faeces' ....