Disclaimer - I'm several seasons behind on the TV series, so feel free to ignore this if you think the series has changed enough recently that the first few seasons have little relevance in this discussion.

But based on what I did see, Game of Thrones is in many ways a very good, arguably exceptionally good TV show. Beyond the spectacular plot twists and the dubious sexposition, and ignoring the question of whether their version of the plot is better or worse, the show excels where it really matters - in the acting and the writing of its characters. Cersei is probably the best example - by some combination of great writing and Lena Headey's acting skills, the character becomes far more remarkable than she ever was in the books, and one of the most interesting female characters in current television. The same goes for Charles Dance's Tywin. On the other hand the TV writers have simplified or even completely deleted relatively interesting book characters like Arianne, but okay, choices have to be made in TV, and it's true Martin might've done better to remove a few characters anyway.

A Song of Ice and Fire is, for all that Martin seems to have lost control of the pace, a pretty good fantasy series, but it's not a stand-out in the same way that the TV series is.