All I've seen is awesome, beachryan. I'm watching the first episodes in a special premiere in a cinema before it airs, and all the things I've heard and seen point to a big success, The wire / Sopranos big for some. A lot of TV critics have alreay watched the first 6 episodes and say it's epic, in the way every chapter is getting better than the previous one. Can you imagine the last chapters with everything going on?
If you haven't watch the 25 minutes maing off, I really recommend you to do so. It's great and if you have read the books you won't be spoiled at all.
A lot of the richness of the books will be lost, of course, but the main plots are so good that can sustain the show pretty well. I agree the 4th book is weak compared to the rest, mainly because it builds a lot of things after the storm of the 3rd book. But also because some of the new characters don't have the strength of the rest and sometimes Martin looses himself in secondary plots or even third level plots. But they own't have tihs problem in TV as they can focus only in the important plots (and even the 4th book has very interesting plots here and there).