When people think that all Latinos automatically have something in common because of language they are forgetting a few things. I don't know if you know this but the Spanish spoken in Mexico sounds different and is different from what Cubanos and other Latin Americans speak. I'm not saying that we can't understand eachother, but there are certain words and phrases that mean something completely different. Also, we tend to assume that all Latin Americans speak Spanish as their main language. We've forgottent that there millions of indigenous people in Mexico, Central America and South America who retain their native language and customs. So, when you think that simply because we supposedly all speak the same language, you've got to realize that some people don't speak that language and that if we do speak the language, it is quite varied in different countries/regions.
I live in California so I really don't know much about the Cubanos, Dominicanos or Puerto Riquenos; I know there are greater populations on the East Coast. But the West Coast has a lot of people from Mexico and Central America. And even though a Guatemalteco will not like it if you call him Salvadoreno/Mexicano, and so on, we still know that we have much in common. One of the main things Central American and Mexican activist collaborate on is the issue of immigrants rights. It is possible for us to work together in the US especially when we live right next to eachother.
"To be a student and not be a revolutionary is a contradiction" -- Salvador Allende, 1973