I agree about Punit's performance today - it had a very creative concept, but choreography (or perhaps execution of choreography in some areas) was not sufficient. While the concept was innovative, the choreography was far from innovative and lacked charisma.
Therefore, in dance, I would say that choreography is perhaps most essential. A well choreographed performance that lacks an innovative concept is far superior, in my opinion, to a poorly choreographed act with an innovative concept. However, good choreography is not sufficient - if you want someone to remember your performance, if you want to truly move the audience, you have to connect with the audience. And the only way you can make that connection, or leave that impact, is when you tell a story through your dance or when you leave the audience with a message through the concept of your act. It takes the performance to a whole new level.
That is why the contemporary style really appeals to me (and many others) because there is always some kind of storytelling going on there. On the other hand, with hip-hop and popping and locking, a lot of the times contestants come and give an energetic and well-choreographed (in some cases) performances, but most of the time you don't remember that performance once the episode is over. However, if you mix that choreography with an innovative concept, it gives the audience something to remember.
No matter what style of dance you choose, you should always use it to tell a story. Technicality by itself is good, but it is not sufficient. I also think a concept gives the dancer more motivation and perhaps even more reason to emote and express themselves through their dance.