According to Entertainment Tonight, Tiger apparently sent her some very racy text messages, at odds with his straight-laced public image. ("Send me something very naughty. Go to the bathroom and [take a picture].")
Tiger doesn't necessarily owe anyone an explanation for what happened at his house on Thanksgiving night last week. But the wages of his continued silence will certainly be the "drip, drip" revelation of other indiscretions, like a grandfather clock marking time until Tiger gives in an makes a live public appearance addressing these issues.