Well, it turns out that the April mailing wasn't the last that I received from National CineMedia.

By this week, I had received a total of three mailings, describing the spectacular, phenomenal, and amazing way in which National CineMedia could host an exciting event at up to 1,200+ theaters nationwide.
But then I got to wondering - why were they sending me these advertisements through the mail?
Why didn't they just arrange to give their presentation once at the previously mentioned 1,200+ theaters? Get their entire mailing list in there, ply us with free popcorn and jumbo soft drinks, and convince us directly about the superiority of the National CineMedia solution? It is perhaps too expensive to host such an event?
Now it turns out that I'm on another mailing list, from the U.S. Postal Service, which emphasizes to me how wonderful postal advertisements can be.
It looks like National CineMedia is proving the U.S. Postal Service's point.