How to add that twist: For this, watch What Women Want
to know what they actually don't. Armed with this knowledge, you could easily get Ben to take Andie to his parents'. There she would be overwhelmed by his changing the baby's diapers, the love of his family for her (turn of Bollywood to sue Hollywood for copyrights?), and other yadda yadda. To complicate it a little further, let them do 'it' once they get back. Now you have the audience guessing the end.Lesson 6:
How to devise the climax: Get drunk, or better still, get sloshed. Since you have already seen The Wedding Planner, just change the wedding to a corporate party for the launch of diamonds. Spill all the beans through acquaintances of the protagonists and have them split up. But wait, the best is yet to come. Ben reads Andie's column and realises that she is the one for him. Airport sequences are out (even "The Parent Trap" had it, sort of). Improvise. And voila - a freeway chase wherein Ben on his bike chases Andie in her cab (is Mahesh Bhatt listening?).