Cooler Master has had great success with the HAF series of chassis designs. This lineup includes the HAF 932, the HAF 922, and the HAF X I had the pleasure of seeing about a month ago. The main idea of the chassis is to offer High Air Flow, as the naming scheme suggests. In all three of the previous versions, air flow was definitely included in the design and layout of those chassis'. Some had windows, some didn't; some were painted black throughout, and some weren't. In the HAF series, there was a nice mix of features, unique designs, and superior air flow in all.
With the previous three incarnations, all the holes were filled with fans, some had great cable management, and all of them had LED lighting. But every addition to the basic chassis also adds cost. At the top of that line, the HAF X will cost from $159-199 dollars depending on where you are shopping. And at the lower end, the 922 will cost you between $89.99 and $109.99. What I see typically coming next is that users swap out the LED lights for another color, or they want to add water cooling, and have to remove fans that are in the way on most HAF models. It looks like Cooler Master saw this as well, and took steps to offer something new.
The HAF 912 is a sort of hybrid chassis in my mind. It keeps features such as a motherboard tray with wire management, room for 200mm fans, screw holes and grommets in place for water cooling, and a similar outer appearance. Obvious changes in the 912 are that it is a mid tower like the 922 and it only includes two of the possible six fans to fill the holes. Then Cooler Master offers new design features like a larger spacing behind the motherboard tray and a removable and repositionable hard drive rack. Don't let the lack of a few features keep you from continuing on, Cooler Master promises an impressive pricing to offset the features it lacks, to give you a DIY version of the HAF series Mid Tower.