I'm guessing it's either because (a) people have actually been reading the licensing terms and other agreements and aren't exactly jumping to sign up, or (b) Microsoft intends to move the whole shebang to the cloud soon and suddenly realized it was still allowing downloads of apps that could be run locally.
While looking at some of the info on their WebMatrix substitute offering I saw this half-truth:
Open Source Web Applications
Made Easier
Open source web apps make it easy to get started developing websites, but they can sometimes be time-consuming to get configured on your computer. WebMatrix makes it simple and straightforward.
Streamlined Install
To get an open source application, you have to find and install all the required dependencies and configure them *just* right before you get started.
But WebMatrix takes care of all of that for you. Choose from dozens of popular open source applications and let WebMatrix do the rest.
Yup. Neatly leaving out just how easy that is to do using
numerous FOSS products and utilities that will do exactly the same thing - and have been doing so for several years now. Which is all well before Microsoft was even willing to acknowledge the
existence of 'open' software. I stopped reading what else Microsoft had to say at that point.
BTW, these days all you need to know is how to spell the name of what you want to install in most cases when using Linux.
Seriously...you can do it from the command line (
sudo apt-get install wordpress), via the synaptic/yum installer tools, or even with one of those pretty new 'software managers' now found in many major Linux distros. All the dependencies are automatically identified and installed (with your permission) if needed. This is what you'll see in Linux Mint:
Free Software from Microsoft. 
