Jonah, as someone who has read the books, I was with Ross — worried that the show was doomed after the three or four exposition-laden opening episodes. But I have been pleased to see friends who hadn’t read the books and were writing the show off early get completely hooked by the end of the season. The “Lesbian Whore” scene was indeed gratuitous (and not in the book), nor was the scene I will call (for the sake of grossing out our readership) the Gay Armpit Shaving scene. This is especially unfortunate because one of the great things the show pulls off is what it leaves off-screen, namely most of the big battles. Most period epics would use the opportunity of a battle to present the audience with a CGI-filled spectacle of the sort that, even when done well (as in, e.g., the Lord of the Rings movies) can start to feel tedious and gimmicky. But in GoT, the biggest battle of the first book takes place off-screen (no doubt at least in part for budgetary reasons). And it works.
Qualitatively, the books are very much worth your time to read, though I don’t know whether that’s true as an empirical matter (what between finishing your own book and Twitter). One good argument for reading them is to get to the major twists and turns to come before the spoilers get to you. I was amazed by how well the books’ fans kept the secret of the end of the first season. All of the novices viewers I know really didn’t know what was coming. But I can’t imagine that will last as the show’s popularity grows (I think of the Harry Potter-hater t-shirts that read “[redacted] dies on page 543″, or somesuch). And without giving anything specific away, I’ll give this meta-spoiler about the seasons to come: No character is safe from death or tragedy, and there is no character you currently hate who you might not eventually grow to love, or vice versa.