Me and a few other folks are also pulling for the Venser replacement. You think a solid Venser replacement (or even an actual Venser remake, somehow) will ever surface? I heard a far off rumor of Phyrexia making some sort of return eventually, and that they'd find a way to bring back the artificer. What do you think? I personally would just love for Venser to not roll out.... he's too much fun right now T_T I mean, he could be replaced with Conjurers Closet.... but that's just not as fun.
Well, the fact that Venser is/was Maro's favorite Planeswalker could help with that, but we can definitely expect to see more of Phyrexia in the future (Maro's intent with Scars block, from what I've read, was to reintroduce Phyrexia as the main evil in the Universe).
But I don't think they would make a replacement for Venser, because that would take away from his uniqueness. I would love to see a U/W Walker, since I'm a big fan of Azorius, but I don't see that happening anytime soon, nor do I see a return of Venser.
And Conjurer's Closet only accounts for Venser's +2, people tend to forget his -1, making all your creatures unblockable until the end of turn (that alone is a game-winner).
Venser is, and always will be, my favorite Planeswalker. My fingers are crossed for a reprint or a new one, but since he sacrificed his Spark to save Karn, my hopes aren't too high.