I watch all sorts of stuff on it. Besides the PPV's, the original content they're coming out with has gotten steadily better. Table for 3 is a lot of fun, Breaking Ground has gotten off to a solid start, the JBL interview thing was cool, and the Austin podcasts are worth a watch. Not to mention the Network special Live events and the NXT specials.
I like to watch the old stuff too. I started watching all the Attitude Era Raws in order starting the night after Mania 14 with the Austin title win. I like to jump around a bit too though. I just started watching some old Survivor Series events to get me hyped for this years, watching 92 right now. There's a bunch of stuff I want to watch still though, I want to chronologically go through the nWo Era Nitros at some point too. There's tons to watch I have a hard time fitting it all in

I love the Network though, great idea and at that price point it's a lot of stuff.