The strip comments were becoming quite problematic. While it made sense for a while to have comments directly on the comic page, the discussions that took place there were often wildly off-topic and resulted in ugly arguments that weren't remotely related to Graham's comic.
The real cost of having comment threads there started to outweigh the perceived benefits. They were being used by just a handful of people regularly, and those folks often used them for reasons wholly unrelated to the Dank/Dunk comics. It was difficult, time consuming, and unsatisfying to try to rein the discussions in week after week, and it still seemed like folks were more interested in posting just to get their name on a webpage ("first post!", etc.).
So, it made sense to try something different. We'll see how it goes.