Erfworld came up earlier as a worthy topic of discussion and comparison to MoR (re: exploiting fantasy rules). Now that I'm caught up, I would have to amend my favorable comments there: Erfworld was good up until the Crowning Awesome of the volcano. Since then, it has been complete crap - abandoned its metafictional pretensions, gone into incredibly boring arcs, etc.

I usually commit the sunk cost hard with fiction series (Wheel of Time comes to mind), but the past year or so of Erfworld has been dull enough that I'm close to just unsubscribing.

EDIT: you know what, now that I've explicitly labeled it a sunk cost, I've realized it really is. I'm putting a 6-month reminder on my calendar, and if the comic doesn't shape up before then, I'm unsubscribing. I probably will - past is prologue.

EDIT2: I also put in a reminder for Bad Machinery which had a similar problem. The reminder fired today (23 June 2012) and on reflection, the last selkie arc wasn't good enough to justify future subscription, so I have unsubscribed.