What happens when Romeo meets Juliet?

When Romeo first sees Juliet in Act One Scene Five, he basically "falls in love at first sight." He basically forgets about Rosaline.

ROMEO

[To a Servingman] What lady is that, which doth

enrich the hand

Of yonder knight?

Servant

I know not, sir.

ROMEO

O, she doth teach the torches to burn bright!

It seems she hangs upon the cheek of night

Like a rich jewel in an Ethiope's ear;

Beauty too rich for use, for earth too dear!

So shows a snowy dove trooping with crows,

As yonder lady o'er her fellows shows.

The measure done, I'll watch her place of stand,

And, touching hers, make blessed my rude hand.

Did my heart love till now? forswear it, sight!

For I ne'er saw true beauty till this night.

But Juliet has not seen Romeo yet. He sneaks up on her, and the first she knows about him is that he has grabbed her hand and has said that if she doesn't like that he will kiss it better. She is pretty quick-witted, saying he can hold her hand if he likes but lay off the kissing. But this doesn't last very long. A few lines later, she is so taken with him that she says, basically, "What are you waiting for?" It was pretty much love at first sight for her too.