Romeo and Juliet is a play about sex, drugs, youth and death. Yes, Shakespeare anticipated the power ballad. He's just that good. It was written probably around the same time as A Midsummer Night's Dream, and the two plays together are more or less a möbius strip of romantic dramedy.
Fighting and fucking are continuously conflated in R&J until you can barely tell which is which anymore. Double- and triple- and maybe more-entendres flash through the verse like the lightning of lovers' oaths, "which doth cease to be/Ere one can say it lightens." Everything happens too fast; this play is like that day that you're in such a hurry to get out of your house so you won't be late for work that you forget your keys so you can't start your car so you have to wait around for the locksmith and you end up missing work entirely, when you should have just spent an extra five minutes in the first place getting your head together.
Every young character ends up penetrated in the end, except Benvolio (Why does he escape? I'm still not sure. What do you think?), and Romeo. Significantly, he dies by the cup, while Juliet becomes a sheath for a happy dagger. A graveyard consummation, then, with a possible Elizabethan pun on 'to die' meaning to orgasm. Is there a possible occult connection there, as well? The cup and the dagger seem pretty ritualistic to me, and need I point out that the play turns on a letter that is undelivered just after Mercutio (a.k.a. Mercury) dies? (Mercutio's famous dying curse is, of course, "A plague a' both your houses!" and the letter never makes it out to Mantua because of a plague.)
Speaking of Mercury, in addition to making sure the mail gets delivered, he's also responsible for bringing dreams to mortals. So, when Mercutio goes off on a tangent about Queen Mab riding around in her hazel-nut shell, maybe it's not just a randomly pretty speech. Not to mention it's a speech about fairies and dreams, which is kind of a shoutout to that other awesome play coming soon to a theater near you.
That other play had something to say about lovers and poets, and so does this one. Marjorie Garber writes that the first lines that Romeo and Juliet exchange are 'love at first sonnet':
If I profane with my unworthiest hand
This holy shrine, the gentle sin is this,
My lips, two blushing pilgrims, ready stand
To smooth that rough touch with a tender kiss
Good pilgrim, you do wrong your hand too much,
Which mannerly devotion shows in this:
For saints have hands that pilgrims' hands do touch,
And palm to palm is holy palmers' kiss.
Have not saints lips, and holy palmers too?
Ay, pilgrim, lips that they must use in pray'r.
O then, dear saint, let lips do what hands do,
They pray - grant thou, lest faith turn to despair.
Saints do not move, though grant for prayers' sake.
Then move not while my prayer's effect I take.
This is a poem that works, which is to say, it gets the poets laid. It's also kind of in direct opposition to most sonnets which are all about how much it sucks not to be getting any. Previously, with Rosaline (and, not to make any biographical conjectures, but when last we saw Rosaline, in Love's Labour's Lost, she was quite possibly a Dark Lady analog), Romeo had exactly that sort of relationship, and was actually pretty bad at making poetry, as well. It's not until he has a willing partner in poetry that he meets his romantic match.
The Rosaline thing also makes Romeo and Juliet's relationship real. Yes, they are young, but they are also undeniably in love. What Romeo had with Rosaline was infatuation, a crush, doting, as Friar Lawrence calls it; what he and Juliet have is the real deal. Which is what makes it all so, well, tragic, at the end.
I really want to talk about Juliet, because for all Romeo's poetry and duelling and whatnot, she's really the heart of the play. She's the sun, for goodness' sake! And yet, for being the sun, she longs for nothing but the night:
Give me my Romeo, and, when I shall die,
Take him and cut him out in little stars,
And he will make the face of heaven so fine
That all the world will be in love with night,
And pay no worship to the garish sun.
She even tries, after her brief tryst with Romeo, to deny the dawn and pretend the lark is the nightingale. She's such a formidable personality by the end of the play that it's painful to watch her being smacked down by her father and betrayed by her nurse. In the end it's her elders, and their feuds and their rules and their hijacking of youth culture - hey, maybe Shakespeare was anticipating the Baby Boomers' effect on the 21st century - ruin her life.