As always, we had our kitty assistant help us with the construction. Since the whole thing is constructed almost entirely with little wooden pegs, we used a lot of wood glue for added stability (not on the kitty, on the Expedit).
The new pieces is 4 by 4, all standard squares, so we could mix and match Ikea's boxes and baskets inside. We ordered what we thought was the same color, but it turned out the color of our original piece doesn't exist anymore. This finish, "black-brown" is much darker than our old Expedit. The lighter color matched better, but this one still looks nice.
Standard sized kitties also fit in the cubbies:
Since the new Expedit was almost twice as long as the previous one, it threw off the balance in the room and caused the cedar trunk to hang out from the sofa by a couple feet - more than enough to cause bruised shins and make the living room seem cramped. We liked the idea of having something there to sit on to put shoes on, so we focused our search efforts on a storage bench. Nothing good came up on Craigslist or our standard stores, and we'd just about given up when I coincidentally discovered a storage bench sold at an online store I'd never heard of, Wayfair, in a home decor magazine while visiting my parents. We came home to find the measurements were perfect and put in the order - isn't it pretty?See how much more storage we have in the Expedit now? The glossy doors and drawers on the Expedit are now permanent once we decided which cubes to nail them into. The baskets are obviously movable. We wanted to keep the left upper edge open to avoid closing the living room off too much, but we have the flexibility to change our minds later. Right now a lot of our household clutter is landing in the empty cubes, but somehow just having them in the cubes instead of lying around on other surfaces makes them seem less cluttered.
The next challenge - figuring out a good way to baby-proof and stabilize a piece of furniture that is not flush with any walls. We have ideas - they involve metal rods and/ or rope. Fortunately we have a little while to figure it out during our sleep deprived state somewhere between infant and climbing toddler...