When I see or hear the words "can't be played," I think really!? When I see spells with mana cost 4+ and anything with

can't be played (excluding creatures,) I think damn, why not just print this at 3+ and X and really go unfun (for everyone else... insert crazy laughter here) Thankfully testing did good at their job.
I have to wonder if this isn't an attempt for WOTC to counter-balance their recent decision to unrestrict Gush. I don't want to think that R&D would just do it to see if Gush may still be broken. No, I'd hope decisions that affect an entire community of players wouldn't be so sloppy. If this is the direction we are heading, then bring it on, but that means we'll definately need to see more card insertions for the format and while we're at it, we'd better clean up the restricted list seeing that the majority has the opinion to do one thing or another with it, including myself. I've always seen the list as a pedestal for a few cards that help define the format and have proven to be worthy.
I do, however, think that vintage will be the format where he will have the LEAST effect...sure vintage is the only real spell-based format left, but it's also the only format where most cards that cost more then 2-3 mana is pretty much unplayable.
I agree about the 2-3 mana range but the cards he does hit tend to be important. As a standalone I don't have much of a concern for this guy, but with other pieces of the puzzles there's reason for an alarm to be raised. I'm thinking something along the lines of Sphere of Resistance and a plethora of other cards that hinder spells from being played .
What really interests me at the moment is watching a possible convergence of archetypes. We'll have to think about it more before coming to too many conclusions on the subject.
p.s. I'm not sure how this would happen, but i wouldn't want to see Trinasphere/Teeg across the table