True Blood is a big hit show for them, a much bigger hit in ratings terms than most of the other cable shows you've mentioned there (save The Walking Dead, which is on a par).
Yes, TB is a hit. I was just trying to say how HBO really hasn't had many shows these days. Each of those networks I mentioned has a big hit (Dexter/TWD) and other smaller shows to support the channel. Outside of TB, I can't think of anything for HBO right now.