We started (re)construction of our house in September of 2008. There's still! things that need to get done inside including the "finishing" of the fireplaces. We put in 2 42" direct vent fireplaces - one in the family room and one in the front room (living room). That's right....42"-ers. Some folks brag on their plasma screens, I brag on my HUGE fireplaces - they type of which you have to go to Panera to see in person. (Note...I think they might actually be too big/hot for a house our size!)
Direct vent fireplaces (for those that don't know) have a piece of glass on the front of them and a 2 chamber flue/pipe that takes hot air out in one chamber and pulls cool air in. It is a pretty slick technology.
The downsides of direct vent are (obviously) it is NOT a wood-burning fireplace. So, you don't get the smell or sound of those. On the positive side, it **looks** like a real fireplace (they've gotten pretty good), it is clean (no dirty wood to bring in) and you can flick a switch on the wall and it fires up. Plus, when putting them in you don't have to hire a mason to build you a chimney.
For us (me), the positives outweighed the negative.
They've been put through their paces this fall and winter - nary a day goes by that we don't fire one up. Maisy's really enjoyed them and heat they throw off - MY GOD, when they're fired up on high the room gets hot fast. She doesn't quite understand them (she lays in front of them even when they are off), but they've certainly changed her behaviors.
Alas, to date, they've been unfinished. No surround nor mantles. All that changes, soon.
We went to the Wilder Mansion in town in the fall and spied one of their many fireplaces. We've taken our inspiration from there. Tile is going up shortly (hopefully) and then we'll get started on the mantles with the help of Nat's dad. Stay tuned for the changes!