Same. I was really looking forward to it each month. I still subscribe to Lost Light but haven't been as drawn in and haven't really read much of Optimus yet. Losing this makes me kind of hesitant to pick up another series just to maybe watch it get canceled, too.
I'm wondering if they'll come up with a third ongoing to replace it (or a string of mini-series, as with Windblade v.'s I and II), or if the focus of Optimus Prime will shift somewhat to allow greater looks at what's going on on Cybertron.