The Urban Dictionary defines... more bromance as "the complicated love and affection shared by two straight males." And while it may be a relatively new term within the American vernacular, coined in the 1990s by writer Dave Carnie in the pages of Big Brother Magazine, bromantic relationships have been intricately woven into the fabric of art and pop culture for centuries.
For those more versed in queer/literary theory, this might be more familiar to you vis-à-vis Eve Kosofsky Sedgwick from her book Between Men, as male homosociality. However, in Sedgwick's book male homosociality must be triangulated through a female--in other words, it can never be expressed openly, but rather as a contest between two males over a woman, though the woman is nothing more than an extra prize from victory. It should be said that Sedgwick was referring to Victorian (et ergo Victorian culture) in her book, though a lot of her theories have held true in modern society (Foucault also posits that, in terms of sex, we are more like the Victorians than we would like to admit--this is where Laura's screen name comes from).
But the movie that the MSN article is written in response to, I Love You Man, seems about as far away from that as possible. (From what I gather, the movie is about a man whose best man and fiancée do not get along, and the "hilarity" that ensues from that.) For one, the homosocial love between men is articulated in the title, and is not skirted around. Second, there is no triangulation through a woman, rather the fight is between a man and a woman over a man, and this fight is overt, not subtle.
What does this mean? I really can't say for sure. On one hand, this seems like it would be a good thing, especially in terms of Sedgwick's work, as the inability to openly express homosocial desire has resulted in many instances of sexism and homophobia. On the other, the whole "bro" cultural phenomenon has always bothered me, as it seems to be focused on excessive, almost to the point of grotesque, masculinity--(bad) beer guzzling, sports watching, flamboyantly heterosexual, not to mention the air of ""douchebaggedness" that seems to surround them. To me, this just seems another way to reinforce heterosexism, because it makes male homosocial desire acceptable between two straight men, and thus pushes non-sexual homosexual homosocial interaction outside of the bounds of acceptable, and homosocial interaction between a straight man and a gay man is almost unthinkable.