A handful of ideas, partly from my own wish list, and partly responding to other posts:

- High ceilings are fantastic. My house has 10-foot ceilings, and I love 'em. I've seen older houses with 12-foot ceilings and they're beyond fantastic.

- Ceiling fans are great. You can feel cooler without needing to blast your A/C. Ceiling fans also work better with high ceilings. You don't need to restrict yourself to the, umm, low-profile models, to avoid any unpleasant collisions.

- Wood floors are good, but make sure they're flat and they're *hard* woods. My house's developer thought he'd be trendy and used some polyeurethane sealed pine 2x6 longboards. They're nice because they don't require any kind of subfloor. They suck because they're easily scratched and they have wide grooves between the boards that accumulate crap.

- Lots of wiring is obviously good, but a wiring closet would be fantastic. Make sure it's got enough power for whatever gear you want to put in there and, most important, make sure it's got an air conditioning duct. You don't want all of your gear cooking itself.

- Wherever you plan on having your media center, think in advance about where everything will go. In-wall speaker cable can make surround speakers much easier. If you want to do a front-projector, then you could hang it from the ceilng and have the video cables in the ceiling as well. Big win.

- I agree with the comments about kitchen storage. If you're half-way serious about cooking, you need just heaping tons of space. A gas stove is also a big win, as is a big, deep sink. Think about having a split sink with a big side and a small side, such that the big side can fit your biggest, deepest pot.

- Think about your shower. You'll probably spend more time there than in the tub. Make sure you've got a shelf of some kind. Make sure two people can fit. Ponder having two separate shower heads so you and she can have different water temperatures.

- Think about the house's exterior surface. My house has this trendy new "HardyPlank". It looks like wood, but it's actually 80% concrete and 20% wood pulp. You can put a nail through it, but it won't burn or rot. You paint it and the paint lasts longer as well.

- Think about where you're going to store your crap. If you can have a basement, that's fantastic. In Houston, where any hole you dig would just fill up with water, storage is a much bigger issue. Many of the newer houses come with "unfinished" rooms, where you might just dump boxes. And, if you later need it, you can always finish the room into another bedroom or something.

- Think about closet space. My house had plenty for me, but when my girlfriend (now wife) moved in, suddenly we didn't have nearly enough.

- Think about built-in storage. Other folks have mentioned bookshelves. If you're into hosting dinner parties, think about a buffet table or something else that can hold all your formal dishes, placemats, and assorted things to take pressure off the kitchen. Likewise, think about satellite bookshelves in the kitchen for cookbooks.

- Think about how people "flow" during a party. The classic problem is that everybody ends up crammed into the kitchen. I like the new trend to have an "open" kitchen where the cooking area is part of a bigger "great room". On the other hand, this means that people can see the mess of dishes piled up in your sink.

- Don't forget artistic touches. Older houses might have stained glass windows, wild-colored tiles in the bathroom, glass brick windows, or heaven knows what else. Newer suburban homes tend to be far too bland in this regard. Don't be afraid of more interesting colors or architectural elements. But, if you're going to go that way, make sure you've got a good architect helping you make the decisions.