I've just watched my way through both seasons. There was never any doubt I was gonna like it a good deal - I haven't read the books (yet) but they've always sounded right up my street. And it is.
Does anyone agree that there's similarities in George R. R. Martin's and Terry Pratchett's approach to fantasy? Both have had the same idea of taking fantasy seriously, not using the 'a wizard did it' approach. I know that might sound weird with regards to Pratchett (though maybe not to a forum full of Pratchett fans) because of all the High Fantasy stuff (Great A'Tuin, wizards etc) and the comedy. But at the heart of both GOT and Discworld is the same thing: what if real people populated these fantasy places, acting in the way real people act?
Anyway, GOT: love it, love the fact that the writers don't think viewers are too stupid to keep up with the million storylines and political manouverings and subtleties of politics. By contrast, I watched the first part of the adaptation of Ken Follet's World Without End the other night. The book is excellent, similar in tone to the GOT series, I think, though based in actual history rather than fantasy. The adaptation throws out all Follet's meticulous research and inserts 'what everyone knows medieval people did' tropes. So tiresome.
Back to the point (again): I'm glad of the great cast (Charles Dance is obviously a stand-out as the not-entirely-un-Vetinari-ish Tywin Lannister; and Peter Dinklage is just awesome as Tyrian); I don't even mind the occasionally wobbly accents (Tyrian and Joffrey speak with an accent that can't exactly be called any known English variety, but their accents are curiously consistent with each others' at least).
Like others have said I have a bit of an issue with the sex in the show. It is a bit over-depicted (I sometimes wonder if the show is produced by 14-year-old boys), but more than that I think there's a bit of a prurient, lascivious attitude to rape and sexual abuse. Seriously there is a TON of rape in this show. And I always have a problem with the 'in the olden days, every woman got raped all of the time' thing.
It makes up for this a good deal by having a load of great female characters. And not just characters who are respected because they're behaving liked boys (Arya and Brienne), but also characters whose female storylines are treated as equally weighty and intriguing (Sansa, Catelyn, Daenerys, Cersei etc).