For some values of "historic", yes, it was

In Froomkin's column today he quotes CBS's Mark Knoller on Bush deputy CoS Joseph Hagin:

It was Joe Hagin's idea that Mr. Bush -- a one-time pilot in the Texas Air National Guard -- fly to the carrier 'Top Gun'-style aboard a Navy S-3B Viking warplane. ... And to this day, Hagin remains "surprised" by the criticism of the flight and the banner -- but still regards Mr. Bush's visit to the ship as "historic."

Historic? You betcha.

It was the first time a president ever dressed up and played soldier in public.