This is something I have seen coming for a while, but today we got the official word that My Digital Studio is being discontinued as of May 31, 2015. This includes the software, digital downloads, and print services. If you have an online account through a demonstrator, you will have through May 31st to access your digital downloads. I would strongly suggest making a backup of your downloads since you won't be able to reinstall them from your account after that date. Honestly, I back mine up by copying the Component and Designer Templates Uninstallers folders from inside the My Digital Studio folder in the Program Files (x86) on my hard drive to an external location. Then if something happens, I reinstall the software and just copy those back in (it's much easier than reinstalling it all). At this point, I will probably make a point of backing up the entire MDS folder instead, as I am assuming I will not be able to download the various updates to the hard copy I have. I would strongly suggest that you do the same.
As sad as I am about this, it is a business decision on Stampin' Up!'s part that reflects the fact that this program did not make enough money to support itself. Since Stampin' Up! is a business that needs to remain solvent and to make money, I support their decision, even though I am sad about it. They have instead chosen to go in a different direction (Project Life) for scrapbooking. I'm working on using that more, though I have to say I like MDS better since it offers for versatility, but that's just me.