Originally a 2chan meme, also known as Four Guys, Gaijin Yonkoma, Reaction Guys, etc. Gaijin being an impolite term for foreigner, translating literally to "outsider." Yonkoma (or 4koma) being a traditional 4 panel comic, usually reserved for gag strips (eg. Azumanga, Sexy Losers etc.)
A Gaijin Yonkoma is usually interspersing 'good' and 'bad' images with two stock reactions. The reaction pictures used show four attendees at E³; a group of editors from IGN responding to Nintendo's E³ press conference. One picture has the four sitting in chairs, with little emotion, representing Nintendo's mediocre 2003 conference (in which the central point was the failed GBA-GC "connectivity" feature); the other shows a similar group cheering wildly, representing the 2004 conference (in which the Nintendo DS, The Legend of Zelda: Twilight Princess, and many other major projects were revealed). Different IGN editors attempted to create a similar photograph for Nintendo's 2006 conference, but to nowhere near the same Internet popularity.
The images have also been used as models for anime characters drawn in the same poses, most notably Akane, Mitsuki and Haruka from Kimi Ga Nozomu Eien. An interesting thing to note is that some people have swapped seats and changed their clothing between photographs, whereas the comic form implies they're immediately sequential.