Twitter

In AZ-TESOL mini conference last Saturday, there was a presentation about using Twitters for learning English in Japan. The presenter mentions that Twitter has just been launched this year in Japan and many students use it as a way to learning English. However, participants in her study only twitter other Japanese, rather than never native English speakers because they are afraid they could not understand native speakers because of their natural and authentic way of using the language (especially abbreviations, slangand idioms), and they could not be understood by native speakers either. She presents some typical errors made by Japanese students, such as translating Japanese into English literally, punctuation problems, inserting Japanese words in English sentences (like な. I don't remember the whole sentence), etc. I call tell that most of these English sentences are organized in very Japanese way. It seems that all students involved in her study consider Twitter a good way to use English in their daily, but the question popping into my mind is that to what extent using Twitter is benefical to them. Is their fluency and accuracy in speaking and writing in English really improved? Will these Japanese English impose an obstacle in the learning process?