Writing Question: Thoughts on Prologues

I’ve been toying around with adding a prologue to my YA manuscript. But have wondered whether it was really necessary.

Here are a few links I’ve found about prologues.

Nathan Bransford has a recent post about prologues. 

Scott Westerfeld’s take on prologues.

Suite 101: When Does a Novel Need a Prologue or Epilogue?

What do you all think? Do you like prologues in books? Or not? 

Of course, I’ve probably wasted enough time thinking about this when I should be finishing up my manuscript, but, hey, anything for the sake of research. I’ve put up a poll on my sidebar and would love to get your opinion. Thank you!