That is good and bad. Because of they start to disappoint they will just DROP, but they are staying consitent with the audience they already have, and that isn't bad
It's still the most successful show on HBO since The Sopranos and Sex & The City. Game of Thrones is probably going to reach higher ratings than TB next season, but True Blood is the most consistent show on HBO too when it comes to ratings. It kept up an astonishing great average of 5 million total viewers for 3 seasons.