The "EXITO" phrase comes from a spanish-speakers video in a serie of comercials about an on-line english course, Open English. According to it's "Who are We?", OpenEnglish was stablished in 2006, and it's companies, with offices in Miami, Caracas, Bogotá, São Paulo y Panamá.

In spanish, "EXITO" would be the equivalent of "SUCCESS" perhaps WIN!.
In this case, "EXITO" would (and should) be treated as a sort of fail to speak english, beliving that one is winning (simply, thinking of win, and failing while doing so)

In these videos, there's always a discussion between the main two characters, one that goes to an institute and the other that leanrs from this site. The comercial tries to emphasize that learning from a book is not very trustworthy because of how that character poorly speaks a very bad english. It's counterpart learning from that web, is shown to speak as if english were it's mother tongue, and make the other one look foolish, if he doesn't make it for himself before.

In this video (titled "El Avión", the plane), the two characters are traveling by plane. The institue guy is quite excited about the trip and asks the other why he brought his laptop with him. He replies that he wants to continue practicing his english, because his on-line course allows him to keep learning even while traveling, as long it has an Internet conecction. In the hotel, he continues, he can keep studying.
The other mocks him and his "cursito" (little course), and openly announces his emotion of going to "Wachington", written in his shirt. Then, the open english guy ask him if he will not practice while they fly. He replies, showing his confidend with a bunch of photocopies and books from his institute.
The plane bell rings and a stewardess appears, asking them if they feel confortable sitting near the exit door, to which the institute guy replies very self-assured "EXITO", and his companion can't help but make a facepalm about his ignorant friend.

It is to note that the video (http://vimeo.com/15293715 is from about a year ago from said online course. Due to be mainly orientated to (somehow older) spanish people, this video didn't appeared to be more than a gag, to show that to learn from books was not the best choice for english, over an online course, then letting the institute guy show his lack of knowledge and/or pronunciation. The publicitys from this company can be found in youtube (user openenglishtv), and mostly in vimeo, with almost 100 videos (user OpenEnglish.com)

Also, a Facebook fan page EXITO was created around 1am the 29th October. To the date it has 16k likes, with varying topics between faping, liking other pages and (horribly) mispelled english phrases, often referencing some of said videos.

The first apparence of this character as a meme (in a vectorized way, as are earlier apparitions of it on the site under the tag "exito" with varying number of "o" at the end) are from Novermber, in Oh… Dios!, a venezuelan site that shows some OC, but mostly translated memes from other pages (such as KYM, 4chan, canv.as, etc). In the 9th, the user "MrVeneco" posted a 4-panels comic (here) showing a typical situation on an english class with the professor asking how to say "nariz" in english and a random pupil answering "no se", as in don't know, and having the question correctly answered. In the 4th panel, appears the face of the institute guy, saying "EXITO" with a cap that says "I (heart) Wachington".

On the 19th january, multimedia comunicator and blogger Felipe Ovalle created the website ¡EEEXITOOO!, a website in which is depicted a flash animation (fragment of the publicity video) of the "institute guy" saying it's catch-phrase while ponting at a big red button that the user can press. In this website is also a donwloadable app for Android, and a promise that there'll be an iPhone app as well.

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also,

ending of another video