Is it the audience that is being tested? Be honest now.

It's an aquired taste. The tests can get quite mundane, though a series as historical as this one is always the exception. Australia Vs the Poms is always (was about to say a hard fought battle, but this is the first time for MANY years the English have actually even come close putting up a challenge, let alone winning) a closely followed match.
One day cricket is much more user/audience friendly. 50 overs each to make as much runs as possible.