Kristin Nelson blogged this week about an author's choice of first or third person, and I am stealing her topic today. The conventional wisdom is to use third person if you have two or more points of view, and first person for a single point of view where you want to bring the reader into the protagonist's head.
I don't know if I'm alone here, but I disagree with the generally accepted idea that first person is more intimate. First person is someone else telling you (the reader) the story. The reader doesn't become the protagonist, he becomes the listener. When I read first person, I feel a sense of distance - especially if the protagonist has a distinctive voice that's vastly different from my own.
I'm not saying this is a bad thing - only that it's the opposite of what the writer may be trying to achieve. And maybe it's just me. Maybe most readers do find it easier to immerse themselves in a first-person novel.
A third-person novel can still be entirely from a single POV, of course, and the trend these days is for close third person rather than the more distant narrator-style POV. This makes it essentially the same as first person, but without the "Buy me a drink and I'll tell you a tale..." distancing effect.