A friend was asking me why there aren't any programs that can analyze a user's pronunciation of words and then give feedback/suggestions.
Indeed, given an accurate phonetic transcription of a predetermined set of words, determining if a user's pronunciation of each word is standard/correct — or, say, determining someone's regional accent — should be trivial.
However, my sense was that Automatic Phonetic Transcription (APT) is not nearly accurate enough to analyze a user's pronunciation in that way — though my knowledge is about 10 years out of date.
Still, it made me wonder: even if APT of spontaneous speech does have a low accuracy — in a context where each expected word (and even possible alternate pronunciations) is known ahead of time, would accuracy conceivably high enough to give a user feedback on pronunciation?
Edit: arjan pointed out that Rosetta Stone claims to be able to give pronunciation feedback; how does such a system work (and how well)?