Controlling the language is part of controlling the culture.  The term "illegal alien" is no longer allowed in some circles, and to the Spanish-language Univision network, even "illegal immigrant" is offensive.  So they're going after the New York Times. 

This is from an article in the  Latino section of the Huffington Post entitled  'Illegal Immigrant' Debate: Univision Takes On The New York Times (Roque Planas, The Huffington Post, October 8, 2012):

...The nation's top-rated Spanish-language broadcast network took The New York Times to task last week in a series of articles on its English-language website, after The Times’ Public Editor Margaret Sullivan defended the paper’s decision to continue using the term “illegal immigrant,” in its pages and online. Sullivan explained her decision as a matter of accuracy. Univision pointed out that Latinos largely find the term offensive and intimated that The New York Times' decision may have more to do with lack of diversity than journalistic ethics.

As the article explains later, Margaret Sullivan "does not set editorial policy for The New York Times, but as public editor her positions can influence style and language use decisions at the paper."

So Margaret Sullivan  thought about it a few weeks and defended the use of "illegal immigrant", rather than adopting the term "undocumented".  Here's what she wrote in an October 2nd blog post:

 Just as “illegal tenant” in a real estate story (another phrase you could have seen in Times articles or headlines) is brief and descriptive, so is “illegal immigrant.” In neither case is there an implication that those described that way necessarily have committed a crime, although in some cases they may have. The Times rightly forbids the expressions “illegals” and “illegal aliens.”

But Univision responded.

Univision shot back in a series of articles critiquing Sullivan's logic and portraying the paper as out-of-touch with Latinos.

And, in a Univision post entitled "The Times Is Behind the Times" [how clever!] the bandwagon approach was utilized:

In many newsrooms where Latinos have a seat at the table, the term "illegal immigrant" has been dropped. NBC, which started NBC Latino this year, dropped the term. ABC, which is part of our new partnership with Univision, dropped the term. CNN, after making recent Latino hires, announced that they prefer to use "undocumented." The Miami Herald and the San Antonio Express-News, which both have a large Hispanic readership, have dropped the term. Even Fox News, a cable channel viewed by the public to be the most conservative network in a 2009 Pew survey, took a step in the same direction when it dropped illegal in favor of "undocumented" on their Fox News Latino site.

Were you wondering about The Huffington Post?

The Huffington Post  prefers the term “undocumented immigrant,” and has avoided the term “illegal immigrant” since 2008.

Then there's The National Association of Hispanic Journalists:

The National Association of Hispanic Journalists launched a campaign to get newspapers to drop the term “illegal immigrant” back in 2006. "It is much easier to dehumanize and to silence somebody when you're calling them an illegal," then-Executive Director of NAHJ Ivan Roman told the American Journalism Review in 2010.

Maria Hinjosa doesn't like it.

On Sunday's edition of "Up with Chris Hayes," journalist Maria Hinojosa echoed the notion that media outlets may decline to drop the term "illegal immigrant" because not enough Latinos have input in style decisions...“I want to know who’s in those style meetings and how diverse they are,” said Maria Hinojosa.

And according to polling,

Almost half of likely Hispanic voters find the term "illegal immigrant" offensive, according to a Fox News Latino poll released this year.