Good question, Ronny

To me it is movement based on the technique and vocabulary of classical ballet, danced by exquisite and beautifully trained dancers, set to music that is listenable, and put together by someone who knows how to take the music, the dancers, a set or backdrop, and lovely costumes and pull it all together into something we want to see over and over again.
The work might have a story and it can be a comedy, a drama, or a romantic fairy tale. Or, it can be purely expressive of the music and totally abstract. But it must have form and reason. It can have movement that is representative of a country, called National or Character Dance, and it can take the classical vocabulary and use it to create a work based on a particular idea or period in history (Billy the Kid, Rodeo, Fancy Free, for instance) by making the balletic movements appropriate to the people in the story.
This question is difficult to answer because it is, of course, a matter of opinion. There are a lot of works being called ballets today which some of us might not consider to be "real" ballets, but then others do. When the vocabulary of the work is based more on modern dance technique or jazz, for instance, is it still a ballet? Is it a "contemporary ballet" as opposed to a "classical ballet"? If so, is it still a "real" ballet? Well, I guess my answer to that is, sometimes ;) I have seen contemporary works which I would certainly put in this category, but then there are a lot which I would not. If I hate the music and think that the movement is ugly, if it is violent or extreme and the dancers are rolling on the floor and beating themselves up and being thrown around, then I would probably not consider it a ballet. But then, that would be only my opinion. Sometimes it just comes down to whether it is a good ballet or a bad ballet, but other times I have walked out saying 'this was not a ballet'.
I think that the impression that the site is about "real" ballet may come from the original intent that it be about ballet only, as opposed to other forms of dance such as modern dance, jazz, hip hop, tap, ballroom, etc. But your question opens the door on the question of what we consider ballet, so, those are just my thoughts on this lovely April morning.