It's been mentioned on another thread about the intensity of this scene, which I totally agree with, in fact, I think it's pretty darn hot! Apart from it being a fantastically passionate scene to watch, it's also, again, amazing to see the character of Ennis and his yearning for Jack, but still with that element of fear - fear of being found out, fear of giving in to his innermost desires - but not being able to help it. If you watch this scene closely (duh! as if you haven't already!), do you see how Ennis is kissing Jack so forcefully and passionately in a loving way, BUT he also is quite brutal, particularly in the way at the end when they finish kissing, and Jack touches Ennis's face one last time, and Ennis quickly pushes Jack's arm away, but can't resist one last touch of Jack's face? I don't know if I'm getting across exactly what I mean, but you know how throughout the film, Ennis was shown to mix his love for Jack with brutal cruelty and violence (the scene before they have to leave BBM, which starts of as playfully loving but ends up with them fighting), I felt you got a slight view of that coming through again, but I would also argue that he almost gave in totally to his desires here, because after all it had been 4 years.
It was also really beautfiul when, during this scene, they stop kissing and just touch, head touching head, not needing words or actions at this point.
I'm sorry if this seems a slightly unclear post - I know what I mean in my head, but sometimes it doesn't always come out right - if you do know what I mean, please tell me! Would love to know what others think about this scene too.