The majority of west elm furniture is MDF, sturdy enough but I would say not that much better in quality than IKEA.
The chocolate color is very dark brown almost black, and is a wood veneer. The white color is a lacquer that scratches easily. The stores usually have swatches of finishes or can show you a different item in the same finish.
If there's a west elm in your area, call and see if they have a display model - some stores have "online only" items in store for this reason.

I'm pretty positive I checked this out in the West Elm outlet when looking for a piece for our foyer. The quality is not great -- as the first poster said, not much better than Ikea. The white finish is really easily scuffed and marred and I wasn't impressed at all. The chocolate veneer is similar to the Ikea "black brown" color. I had hoped it would be richer.

I've had both Ikea and West Elm furniture and found that Ikea is every bit as good for less money. Perhaps an ikea expedit turned on its side or something similar?

I have also found that a lot of CraigsListers treat their furniture pretty well--see if you can get a bargain for one of them on there! Both brands come apart pretty quickly and easily for transport.

West Elm is the same quality as IKEA. It's cheaply made, entry level, college student/striver furniture. Looks nice for a while, but not durable. You get what you pay for.
You can find excellent quality, SOLID WOOD storage on Craigslist for very reasonable or possibly free. Just look in the FREE listings, there are many nice & generous Craigslisters. Good luck!

West Elm is ok for minimally used furniture. The quality is exactly the same as IKEA, as others have mentioned.

Why not go for something like: http://www.roomandboard.com/rnb/product/detail.do?productGroup=6125

Similar price point, and the quality is excellent.

I'm getting my handy-contractor brother to build me a longer version of this! The wood is only costing me about $100.00.

I bet you could find somebody on craigslist, maybe a retired builder/hobbyist who would build you a sweet real one for way less!

You are so smart to ask this before buying sight unseen. I own one piece of West Elm furniture, the (unfortunately, no longer made) Jay Desk, and assumed that all of their products would be of equal high quality. Sadly, not so - I fell in love with their Tripod Table online, but happened to have a chance to check it out in the store before buying it and was really disappointed. I'd put it a notch *below* IKEA quality. So, like most chain retailers - I've concluded that West Elm is terribly inconsistent.

Not sure about the dimensions of the West Elm item, but I have been looking for a small media solution also for my living room. Done a bit of browsing at IKEA for a solution, and their Besta line is pretty decent with a lot customizable features.

This "shelf extension" is about 24" wide and 15" tall. http://www.ikea.com/us/en/catalog/products/20134051/

This frame is also 24" wide and 25" tall. http://www.ikea.com/us/en/catalog/products/00134052/

You could add legs to make them taller, or stack them up to add additional shelves. They also have a wider version, but perhaps this will get you thinking a bit about options!

Keep in mind these are not solid wood. The Besta line is also on sale now if you are part of IKEA family (free program).

I have it in white! ..and absolutely love it. There's a tiny bit of shine on the actual shelves, but not too much--the perfect amount truly! Also, very easy to put together!

I have no idea about the quality of the piece you are asking about, but check out Room and Board (they may have a store in your area). I would not purchase some of their upholstered items, but their case goods are often solid wood or steel and fairly priced. I have some of their pieces and have been very happy with them (and they seem to have some products that are similar to, if not identical to, what you are looking at from West Elm).

@Torgny

Why wouldn't you buy some of R&B's upholstered items? Just curious as I'm thinking of getting the Anson sofa.

i think it's made out of chipboard/ particle not MDF.. I could be wrong though, if it's made out of fiberboard then it should be extremely heavy with minimal racking.

I have to agree with most of the posters - West Elm furniture is beautiful for show, but not the best quality. I have the white laquer parsons desk, and the finish is damaged SO easily. I also bought a rug from West Elm that I love, but the quality is not as high as I think it should be for the price. I continue to buy decor accessories and bedding there (great quality bedding), but will not buy furniture or rugs again... if you still have doubts, look at their facebook page for feedback from customers.

I actually have two of these! The smaller one and the tower one. Both are in the white lacquer. In addition, I have the desk in a cream colored lacquer. The desk and smaller shelf are about 4 years old, and have moved with me 3 times now. Both are in PERFECT shape, and I am not easy on my furniture. The larger shelf I got about a year ago. The large tower is very heavy, but incredibly sturdy. Right now there are about 100 books and a set of old vintage speakers with a receiver on them, and the shelf is holding up just fine - has been for years now.
As far as WestElms's quality overall, I find it to be WAY better than ikea. It may not be top shelf DWR, but it's certainly good quality.

Moot point. They don't sell the low bookshelf anymore.

I had a terrible experience trying to return a catalog item to West Elm. For that reason, I personally would not purchase something sight unseen.

I hear Crate & Barrel's furniture is much more durable?? They may have something similar. And, I'm a huge fan of Pottery Barn. Their furniture is really good quality as I have several pieces. The only thing is I think you may be looking for something a little modern than what PB may offer.

I have a friend who has this shelf and it's not held up very well. Of course, I don't know you, or how hard you are on furniture, but they use it for display, mostly ceramic things, and a few books. It's a child-free household, and they have two cats. The biggest issue it that the finish has given way, and it seems to sway ever so slightly from side to side. Of course (again), I don't know if they've been sitting on it, or moving it about the house, which would loosen the joints.

I've been looking for a piece of furniture with a similar look and function. Right now, I have an IKEA Linnarp TV console (discontinued), and after 4 years, it's starting to show it's wear and tear. I've found some nice cabinets with similar dimensions, the best being from Crate and Barrel:

http://www.crateandbarrel.com/pilsen-52-media-console/s636897

http://www.crateandbarrel.com/furniture/bookcases-towers/shift-black-74-bookcase/s254374

Or this from Overstock.com:
http://www.overstock.com/Home-Garden/ETHAN-HOME-Myra-TV-Stand/6743629/product.html

I find west elm to be of better quality than Ikea. The negative comments would indicate a lack of familiarity with their products.