The page indicates that subscriptions will be honored on the Paizo site as credit with some options as to how to use it, although they don't go into details about what the ooptions will amount to.
As to why they did this, it's all part of the ongoing trend in the publishing industry as a whole, moving from print to electronic. While it's been true on a larger scale for OGL and more mid-size corporations in the gaming industry, other publishers, especially business industry publishers like Thomson and Lexis have been moving over the last several years to minimize their print publications, divesting themselves of a number of products while simultaneously moving to improve and increase the diversity and availability of their online resources.
That said, I'm sorry to see the magazines go. There's a lot for Wizards to live up to, as far as usefulness goes, and one has to wonder how much their online publications will restrict the free content available on the website. Will there even be a free Wizard's website, beyond maybe a products list?
