Just a couple of quick things for (finally) getting the iPhone to recognise some of the more colourful words in the English language:
- Settings > Keyboards > International Keyboards > Add New keyboard... > English (UK). Doesn't appear to change the layout at all, but stops the autocorrect from trying to put a 'z' in where an 's' should be.
- Settings > Keyboards > International Keyboards > Add New keyboard... > Chinese - Simplified (Pinyin). Once you've put this, or certain other keyboards (appears to be ones that use different characters), you will then see a new option under Settings > Keyboards called ... wait for it ... Edit User Dictionary...
Finally, my iPhone can realise the glory of a correctly spelled fuck.
Props to user modular747 on the Apple Support forums for the (crazy) steps required for Edit User Dictionary.