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今日ですね always sounds a bit funny to me because I keep thinking about it as "it's today, isn't it?" (and then the answer could be "well, yes, it's not yesterday or tomorrow, so it's today":-))
Why didn't the speaker say こんにちは。えっと、今日、日本についてお聞きしてるんですけど?
What's the difference between 今日 and 今日ですね?