If you saw "Un Homme et un Femme" and loved it, do yourself a favor and don't watch this one.
I believe Lelouch needed a few extra bucks because this film ruins the story of the first. Did we need to know what happened to Anne and Jean-Louis 20 minutes after the first movie is over? Not really.
And even if you consider this film alone, its still a very boring flick. And pointless. The story makes too many detours with their every day life: what they do now, how they evolved, and constantly needs the support of the first film to make a little sense. At the end of it, one is left with a bitter aftertaste of having betrayed the beautiful first story. Second parts are seldom good, and this movie proves it perfectly.