Today was a good day. That could be a wholly unremarkable statement but in this case I don't think it is. If someone asks you how your day was and you tell them it was a good day, that seems unremarkable (though not a bad thing). When you can proactively say: "Today was a good day" without being asked it seems that you are taking that extra step to be explicit about it. The day itself doesn't have to be remarkable but sometimes the acknowledgement of it is. Remarkable, unremarkable, marketable... I don't care. Today was a good day.