The origin of this gesture is said to be the orthodox way of crossing yourself, with three fingers instead of the entire hand (referring to the Christian Trinity of the Father, Son and Holy Spirit).
That is not unlikely but the actual othodox crossing is done with three fingers together, not spread. The spreaded Serbian salute could however be seen as an exaggerated version of the hand used in crossing. It is as if the Serbs, in this gesture, stress their difference from people that cross themselves with the thumb touching the fingers in opposition (catholic Croats?).
The Serbian salute is made, for example, by fans and players to celebrate sport victories. Members of other ethnic groups, especially Bosniaks and Croats, are said to find it provocative. So, it is effectively a symbol of national and/or ethnic identity.
Now, if you rewatch the footage from songfestival, you can see Marija and other members from her group giving the salute regularly when they receive points, or when they are cheering after their win. The same goes for cheering crowds in Belgrade.
In a way I feel that this salute is similar to waving a little flag, which is not criticized among songfestival contenders. However, one specific occasion sparked a bit of commotion. After receiving 12 points from Bosnia Herzegovina Marija made the Serbian salute. Some people were offended because Serbian troops also flashed this gesture around on their military campaign there, reminding people of the atrocities commited there by the Serbs (and others).
More generally, the Serbian salute was often used as a nationalist sign before and during the Yugoslav wars.
When she was confronted about her salute Marija Šerifović was irritated and said she did not have to explain her behaviour. Serbian commenters on the web are also quick to make light of the matter or suggesting critics to go to hell. Is it justified that the criticism is so easily shrugged off? I think it is not justified. I think Marija and other Serbs are well aware that they offend people with the gesture.
Because it is not the first time this story was told. It all happened before in exactly the same way, in 2003, with a Serbian basketball player in the NBA called Vlade Divac. He also flashed the Serbian salute to cheer or greet his countrymen. And when he was confronted by critics he also downplayed it and shrugged it off, much like Marija now, although he seemed to be well aware of the meaning and use of the gesture in the wars.
Read the full story for a good background on how to interpret the modern use of the Serbian salute. It also gives a good impression of how it was used by the Serbian militia. Here is a paragraph that I think captures the essence:
The symbol is associated with the Serbian Orthodox Christian Church, and experts say it represents the Christian Trinity of the Father, Son and Holy Spirit. But, through decades of ethnic strife, the gesture took on a nationalist meaning. It is also associated with the “Three C’s” from the nationalist slogan “Only Unity Will Save the Serbs” (In the Serbian language, the words “unity” “save” and “Serb” all begin with the Cyrillic letter “c” the equivalent of “s”) It became used as a threatening weapon, an “in your face” gesture aimed at terrorizing non-Serbs.
So, are we to believe that people like Marija, who appears to be an intelligent, informed Serbian, are not aware they are causing offence with the Serbian salute? I find that very hard to believe. Sure, the songfestival stirs up feelings of national pride, and a lot of flags are waved. But this should be mixed with growing respect for eachother. That is the purpose of such events, much like the Olympics. I can only see this gesture as a childish boasting of her own Serbian identity mixed with a display of contempt for neighbouring peoples. Not illegal perhaps, but quite rude and highly offensive.
The only justification that could be made is that history is not as we think we know it, that the Serbs were actually also victims of the war, that this should be acknowledged, and more of such excuses. But even such a view (which I do not share) does not take away the childishness and rudeness of the act. It just hurts the eyes. Elsewhere: Samaha