Actually, if I remember correetly, the Sentry DOES have at least one thought balloon in one of the first few Mighty Avengers issues after Civil War, during one of the fights vs. Ultron. It's kind of hidden because it's attached to a normal "speech" balloon, but it's there.
--Previous Message-- : Someone on another board went back and : checked: Bob has had no thought balloons. : Didn't Bendis say that this was the way to : tell who the Skrull in Mighty Avengers was? : This either means Bob's the Skrull, Bendis : didn't feel he could do justice to an insane : character, or it somehow points to Lindy. : : Just love how cut and dry yet simple all : this is... : :