I'm going to write about the HUGE (and the subtle) differences I've encountered so far between American and Spanish cultures.
1. Toilets. These are important no matter where you go. Here they're small and uncomfortable whether you're at the airport, in a bar or in a theater. I wonder what logic goes into determining how much water to maintain at the bottom of the toilet after every flush? Spanish plumbers decided only two inches at the bottom were necessary.
2. Meals. These once-simple necessities have reared their ugly heads to show me their true significance. First of all, timing: Spaniards eat a light breakfast (sometimes just coffee), a snack at noon (yogurt or an apple), lunch around 3 (which is typically entree and a pastry or piece of fruit for dessert), merienda around 6 (time for tapas!), and dinner around 9 (almost always two plates and dessert). As for content: it's not a meal without pan (bread), which is typically a fresh-baked, long, crispy loaf of white bread. The typical plates are: paella, any kind of seafood, any kind of pork, any kind of beef, chicken, bean soup, chicken noodle soup, chickpeas, tortilla (which looks like an omelet with potatoes), rice, and/or fried potatoes. They also hardly ever eat vegetables...I'm not going to gripe much more on that subject though...and the occasional salad consists of Iceberg lettuce, olives, and tomatoes drenched in oil and a spot of vinegar. Going out to eat at a restaurant - even the cheap ones - means it's a 3-course meal - even if you didn't feel hungry enough for an appetizer or dessert - and if feel too full to finish your second plate, the option of taking it home in a styrofoam box is simply unheard of. It's a bit of a damper on my old habit of going out to eat, ordering just one (always gigantic) plate and bringing back the untouched half for leftovers the next day...
3. Sex. I've been startled on countless occasions by how much this once-notoriously Catholic country is cool with sex. It's totally unremarkable to have breasts on the TV (no matter what genre the show), hotels ads showing dominatrices in action, and documentaries with cartoon characters getting erections and boinking (yes, the sound effect was literally "boink") on the bed along with interviews of porn stars interspersed with clips demonstrating their work.
4. American pop culture - in Spanish. They have more American songs, TV shows and movies than I can count. Just today "Walker, Texas Ranger" was on while I was eating breakfast, and even Chuck Norris had a Spanish voice-over. I've watched "Avatar" and "Star Trek" in Spanish, and on the bus I've heard Beyonce's "Si Yo Fuera Un Chico" ("If I Were a Boy"). Not all musicians could record Spanish in place of the original, like Michael Jackson or The Beatles or...Lady GaGa...but for the most part, the American/British music I've heard here is in Spanish. I've been warned by a friend that they also use Spanish voice actors for currently running seasons, too - in other words, I need to find a way within the next two weeks to download LOST online or I'm going to be clutching at my dictionary for half the episode! As for the accents, some translate and some don't. For example, Chekhov's voice actor in "Star Trek" sounded very Russian by rolling his R's...for every single consonant. But doing a Southern American accent in Spanish is simply impossible (no Sawyer, no Bones) and the Scottish accent comes off stilted at best (sorry Desmond, Scotty).
5. Websites. About downloading LOST - ABC.com, Hulu.com and a plethora of other websites don't have international rights...so you can't watch their videos anywhere else but the States. It's kind of devastating the first time you click on a video (for me it was the finale of the most recent LOST season) and realize it's never going to leave that black frame...