Pronounced “La-teen-ex,” Latinx is a gender-neutral term for people of Latin American heritage. By dropping the traditional –o or –a ending at the end of the root word ‘Latin,’ Latinx encompasses those who identify outside of the gender binary, such as transgender people or those who are gender-fluid. Lately the term has been popping up in mainstream outlets like The New York Times, Washington Post and USA Today, and it is increasingly visible in Hispanic media as well.From here. The New York Times also has an article today on the term.
While the people pushing for its greater use have good intentions, one reason not to use it is that lots of people don't know what it means. And, a word that isn't understood never serves its intended purpose. I wasn't entirely sure exactly what it meant until I looked it up today, although I had a pretty good idea what it might mean.
Time will tell whether it becomes accepted in common usage in the long run or not. I'm not really opposed to the term, but I'm also not convinced that there is a compelling need for it (a concept that can be expressed in other ways, albeit, less compactly). If it becomes standard usage in "Standard American English" or even in academic circles, I will probably use it when the occasion calls for it. If it turns out to be a short lived fad that never really goes anywhere, I may not end up using it.