Each time we say the Amidah, we include the modim prayer. In it, we list things that we must speak about -- our lives that we place in God's hand, our souls which are entrusted to God, God's miracles and God's wonders which are all around us. We list them but don't really talk about them in any detail.
We introduce these items by saying "nodeh lecha, un'saper tehilatecha" we will thank you and we will speak your praises.
The modim prayer, itself, is clearly a "thank you", apart from the mentioning that we will thank -- it is the thanking, itself; but is there a separate obligation to speak of God's praises?
Fulfilling sippur yetziyat Mitzrayim requires a text other than one which says "we will tell of the Exodus." Does Sippur tehillot Hashem also require a distinct text?
The idea in Modim comes from Tehillim 79:13, "וַאֲנַחְנוּ עַמְּךָ | וְצֹאן מַרְעִיתֶךָ נוֹדֶה לְּךָ לְעוֹלָם לְדוֹר וָדֹר נְסַפֵּר תְּהִלָּתֶךָ" which seems to indicate a commitment and obligation in each generation to speak of God.
Is this speaking a separate obligation? If so, is it fulfilled simply by recalling that we have to do it or is there a separate way of fulfilling it?