Amy Finnerty in the WSJ ($):

No soft focus here. An aging couple (the therapist and her retired husband) enacts foreplay to a jarringly incongruous pop music soundtrack. A middle-aged mom, neglected by her husband, watches forlornly as he engages in the auto-erotic act that he prefers in lieu of sex with her. A more assertive wife — one driven by baby-lust — uses a venerable method to procure sperm from her husband for a volume assessment, in one of many scenes in which the camera angles are not so much candid as utterly unabashed. An exhaustive catalog of sexual acts is graphically depicted and no detail that can shock is kept off-camera.

Shales:

The goal is verisimilitude, not titillation, but that’s not to say this is a stuffy or scholarly look at sex. It’s just an impressively honest and open one.

Allesandra Stanley in the NYT isn’t buying what HBO is selling:

The series bores deeply and single-mindedly into the marrow of marital relations, and it does so with sympathy and insight. It’s daring but not revolutionary. “Tell Me You Love Me” is a little like a jazz musician who wants to scandalize the audience but still be asked to play in the orchestra at the country club dance.

Variety’s Brian Lowry has his doubts, too:

Yet those positives are leavened by the program’s deadly sincerity and almost total lack of humor, as well as moments when the sex’s graphic nature proves distracting (as in, “Hey, were those his balls?”), disconnecting you from the show’s reality. In that respect, “Tell Me” compares unfavorably with HBO’s “Big Love,” which also tackles the vagaries of marriage, albeit from a more exotic starting point.