1. A method of optimizing recognition of a speech utterance from a user with a distributed speech processing system comprising the steps of: (a) training one or more speech recognition models for recognizing speech utterances in a first natural language in a first training operation; wherein said speech recognition models are implemented as part of a speech recognition engine executing on a network server system of the distributed speech processing system; (b) training said one or more speech recognition models in a second training operation, said second training operation being based on additional samples of speech from a group of persons employing said first natural language and residing in geographic regions served by the distributed speech processing system; wherein recognition of speech utterances during a speech recognition process is optimized for a geographic region by using one or more speech models which include variants of words to be uttered by users of the distributed client-server system.