Being able to access newspapers and magazines on my kindles was something that always made me return to them after kobos. I now have a Kobo as well as a Kindle (to access epub library books that cannot be sent to the kindle).
Once this is taken away, the only thing tying me to the kindle is the excellent Scribe with its beautiful 300 dpi screen and really nice handwriting ability and the send-to-kindle functionality.
When Kobo release their next large screen reader, I'm sure it will have the improved screen, and I suppose using Dropbox is pretty much as good, if not better, than send to Kindle.
At that point, I don't think anything will be tying me to Amazon any more. I appreciate I am in a minority of approximately one, and therefore do not factor into Amazon's business plans.
But, the newspapers and magazines were really the thing for me that differentiated the Kindle from the other ereaders out there, and I will be sad to see this program shuttered. In order to prepare for this event later in the year, I have weaned myself off using the kindle to access newspapers and canceled my remaining subscriptions.
It really seems a most strange time to take this step, just when they have finally released an ereader with a screen that is actually big enough to read periodicals on.
I know it is because they use an extremely old format related to mobi, but it's a shame they basically can't be bothered finding a different way to send them - I would even settle for PDF format! I know it's all about the $$$$$$$.
Once a company gets to the behemoth size, the cheese-paring starts.