I like ’em.
They’re like a clue. They get my brain working right off the bat – I ask myself: how will this matter later on? I like them particularly if they differ in atmosphere and tone from the first chapter – the juxtaposition creates tension right off the bat.
The reading I’ve done says prologues should be in a different point of view than the rest of the story, or perhaps occur a very long time before the story begins. They should have some feature that differentiates itself from the rest of the story.
I gather many agents don’t like them. I suppose this to be because they’re used as dumping grounds for exposition and backstory that should be worked into the story in more subtle ways.
Anyhow, I’m keen on mine. We’ll see what happens.