Um... if you started a character in Ul'dah, you would have met Thancred much earlier and would have known more about him. Uldah characters get Thancred, Limsa get Ysh'tola, and Gridania get paplymo and Yda.

Also, Thancred was an important character in 1.0. Also, they DO plenty with it later on in the MSQ, and refer back to it throughout the 2.X storyline once Thancred has recovered. Also, Thancred is with you the whole time you are investigating Ifrit. Remember when you were wearing poor person clothes and trying to get kidnapped? I remember that, and I did the story 2 years ago.