On the main floor, we have high ceilings and gorgeous wood moldings and doors in the living/dining/foyer, so I'm going with lighter colors to show off the dark wood. The living room is going to be a pale, olive-y green with cream colored sheers to keep it very light and not hide the full-wall woodworking around the curved bank of windows in the front. The foyer is going to be a warm tan. The dining room is going to be a very traditional red & gold scheme, with gold walls and red drapes/accents. The kitchen is very large and bright, so I'm going with a sort of French country look - white cabinets, buttery yellow walls, blue accents.
The office will be the one break from traditional on the main floor - dark blue walls, white accents, white, blue & orange team-logo carpet tiles, and Detroit Tigers memorabilia framed on the walls. DH doesn't know this yet, but I've already picked out a Lazy Boy to go in there, that has the perfect look and color, just like the worn leather of a well-loved baseball mitt.
Both bathrooms are going to be the same color, but with a different look to each. They're going to be clear-Florida-sky blue (inspired by a WDW photo

) with white fixtures. For the downstairs bath, we're installing a tin ceiling and framing some of my castle and Spaceship Earth photos as artwork. The upstairs bath is going to be gutted and rearranged so the plan there is apt to change, but I think the walls will be the same blue with probably white tile on the tub/shower surround and an almost peacock feather looking shade of mixed color glass tile as an accent.
The rest of the upstairs won't be so traditional. DD7 wants a Hannah Montana room, so she's getting turquoise & purple walls with the swirls/butterflies at the corners. We made DB's crib into sort of a canopy bed using an old-fashioned shower curtain rod like you'd use for a claw-foot tub, so that DD7 can close the canopy if she wants to read in bed after DB is asleep. The new curtain for her canopy and the window treatments will be silver and semi-metallic.
DS11 wants a "rock & roll" room. His walls will be light grey and his furniture is black metal (dorm room type stuff), so the only real color in the room will be red accents in the bedding/curtains and in his guitar-shaped CD rack. I'm going to frame some of my old album covers for him, a few of which I've gotten signed over the years, so that will be the "artwork" in his room.
Our room will be a warm tan with dark red & chocolate brown accents, in sort of a very subtly Asian-inspired look. I'm pulling the colors from a comforter I bought right before we decided to move, so we're sticking with the same basic look as we have now because I like my new comforter and don't want to cover or replace it yet.
The room I'm most looking forward to decorating is the attic space. It has a short, 5' door going in and while an adult can walk comfortably in the middle of the room, the ceiling slopes off to make it kid-height for most of the space. We're building shelves into both sides where the ceiling gets too low even for the kids to walk and decorating the whole room in a Fairies theme. Tink green walls, butterfly Christmas lights strung along the ceiling, beanbag chairs for reading, and just an overall very girly space for their playroom.
DS's playroom is in the basement, and other than installing/insulating a raised subfloor, building shelves, and laying that rubberized garage/kids space puzzle-look flooring tile, I have no involvement down there. I promised DS he could choose colors and the overall look for that space, since it is his "cave" for his video games and such.
As you can tell, I'm not afraid of color! The house we're in now was all white when we moved in, and the first thing I did was changed that - forest green living room, cotton candy pick girls room, brick red master bedroom, and the most flashy of all, DS's room painted in red, blue & yellow with flames on the walls inspired by Jeff Gordon's paint job at the time. I'm toning it down a little at this house because I don't want to detract from the architectural features and the natural beauty of the house, but it'll still be pretty colorful when I'm done.