17. The machine-readable medium of claim 11 wherein said calculating said likelihood of pronounceability is conditional upon said portion having more than a threshold number of characters.
18. The machine-readable medium of claim 17 wherein, if said portion does not have more than said threshold number of characters, said determining said pronunciation of said username further comprises generating a phonetic representation of each character of said portion pronounced individually or generating a tokenized representation of each individual character of said portion suitable for interpretation by a text-to-speech engine.