Niku asked.
This seems to be normal, from my experience. Dictation works by sending your text over the Internet to an Apple server where the conversion into text is made. The result is sent back to you by the Internet and displayed in the text area of your open document. There seems to be a limit to the amount of text you can continue to dictate before the system stops taking any more and immediately returns the text that you have recently dictated.
The answer is to dictate a sentence or two, then double-press the fn key, then carry on dictating when your recently dictated text appears, which it does within a second or so.
I find that Dictation works best when you speak more slowly than you would with a normal conversation and you need to enunciate each word clearly. For example, if you dictate the phrase "next person" by saying "nex person", you will not get the word "next".
It also works best with ordinary conversational sentences. It is not so good when dictating more complex business or technical passages. However, it can surprise. Try saying "thoo sidd-id-dees". It recognises the name of the ancient Greek philosopher Thucidides!
