Jeff Rowland announced on his site that Wigu will end this December 31st. He also definitely hints at a future series to come:
I want to keep the premise of the new series a secret until it actually launches, and I trust it will be pleasing to both long-time readers and new readers. Trust me. It will be good. In the meantime, I will be working furiously on the new project, which is scheduled to launch on 17 January, after a period of intense intensity.
It’s worth noting that Rowland once “stopped” his previous series When I Grow Up and replaced it with a series called Project Thingy only to return to When I Grow Up.