Post Office B2B magazine

The U.S. Postal Service is becoming a B2B publisher. "Deliver" is a bimonthly magazine aimed at executives in the direct-marketing industry. Some 350,000 copies were mailed this week, the post office says. That seems to be an extraordinarlily high number. PrimediaBusiness' "Direct" magazine, which serves the same market, has a circulation of only 46,527. So I'm left wondering if the postal service understands the "controlled" part of controlled circulation.
Addendum: Rex Hammock at Rexblog wrote to tell me about another, more detailed article about "Deliver." In this piece, the reporter says the magazine will send those 350,000 copies to "CEOs, corporate marketers and their creative agencies." That may be a broad enough pool of people to account for those circulation numbers.