So if you're still with me after that little parenthetical party I had up there, I'll explain the porteno way of speaking.
Rule 1: all "ll"s and "y"s are pronounced kind of like the English "j". So the phrase "yo me llamo mark" sounds like "Joe me jamo mark." There is actually kind of an "s" sound mixed in there too, kind of like a "shja"
Rule 2: Instead of using the tu (you informal) form of verbs, people use the vos. To make the vos you basically pull the r off of the infinitive, add an accent to the second to last letter, and add an s to the end. So the vos for hablar is Hablás, and for poder it is podés, not puedes. Commands are also different but other tenses are the same as the tu.
Rule 3: People use their hands a ton while talking, and there are 3 or four (or three or 4) key gestures that people bust out all the time. these include pointing to an eye, putting the tips of all your fingers together pointing upwards and pumping your hand up and down, and, of course, the under the chin "que se yo" hand flick.
Anyway, about two weeks into my trip I started really catching on to argentine style speaking, and I began to love it. The week before I left I had a dream that I was in Mexico somewhere trying to converse with some of the people and they just kept laughing at me and mimicking my "shja" sounds while telling me they had no idea what I was saying. It was the worst nightmare I had during the entire trip! Haha. Or should I say, Jaja?
So I leave you with these: a couple examples of the vos in advertising around Buenos Aires.
This one reads: "Senti el sabor de vivir!", or "Feel the taste of living!" That's right, the taste of living is very similar to that of high fructose corn syrup.
This sign doesn't even have the vos in it, but I had to put it in because it cracks me up. Poor little Juanito was just trying to get across the train tracks when all of a sudden that bipolar Zeus flew into a rage and decided to hurl a fat bolt of lightning at him. And note where Zeus aimed-Ay yai yai!