Anyway, to answer the original question,
I think the two will think they are alone and will start to move in for a romantic kiss and then BAM they get interrupted by shikamaru or sai or something and it will turn out hilarious. And just the fact that they were about to kiss will be the confession and the cause of more tension, hehehe.
Also, the first move has already been made: :thumbs:

I love that Minato smile


Also note the look on her face in the picture. Its that dreamy half lidded expression, gals get when their in that romantic mood.