A friend of mine create a simple, but really good android application.
This simple application allows you to update your twitter status talking instead of typing. After the text is recognise you can amend the text before uploading to your twitter status.
Search for twitalk in your Android market, and start to use it.
Or go Appbrain to download the app, I hope that is useful for you and you will help my friend as well. Spread the word.