Being in Rome one hears a lot of address, lectures, homilies and so on from various local and international ecclesiatical figures, academics and ordinary clergy. Also, being in the City one probably also hears these people make more direct reference to what the Holy Father says than one would if one heard them speak elsewhere. (I don't mean anything negative or snarky about that...) Anyway, it occurred to me that (in my experience) out of all the Holy Father's speeches and writings since his election, the three sources most often cited by others in homilies, symposia, etc... are (in no particular order)
1. Deus Caritas Est - it's no surprise that his first encylical should attract so much attention
2. His Homily at the Mass of Inauguration
3. His Christmas Address to the Curia
Now, that's purely anecdotal evidence, but I think that those three documents give an indication, if not of what the Holy Father is saying, certainly of how the Holy Father is being heard and what others think is of most significance in what he has said.