I'm always a little sad when a character, be it hero or villain, who once had an entire series or event story line connected to it, becomes a fill in story stopgap. Parallax was once a major super villain that entire story arcs and revolutionary events in the DCU hinged upon. Now, the "yellow lantern" mascot can possess one of the universe's most power superheros and have its machinations wrapped up in a tidy two issues.
SuperParallax vs. Sinestro
That isn' to say that Keith Champagne's story isn't a good one. It's just that long term DCU readers will remember Green Lantern Rebirth and The Sinestro Corps War and the wonder and awe they inspired. Green Lantern was pretty much done as a property before Geoff Johns resurrected the character with the two aforementioned story lines, of which Parallax was a major component. Here though, Parallax does all his damage and is bottled up nicely and rather easily by Sinestro and Superman after a little throw down between a Parallax possessed Superman and Sinestro. Again, fun stuff, but fluff stuff if you catch my drift. Sadly, Parallax is now on par with Doomsday. He's basically a nostalgia tool who's trotted out every now and again to catch the aging reader's eye and maybe sell a few books in the process. Yes, the point can be made that resurrecting Parallax for a few issues might spark further sales of Green Lantern Rebirth or Sinestro Corps War by proxy, but that's not exactly a sound strategy roping in new readers.
Superman is still a fun read, even when a fill in story between major arcs pops up. I'll keep reading.