I'm sure a lot of people watching who haven't read the books are lost. It's pretty confusing to try to sort out who's who.
I kind of feel like this is one of those things that people who have read the books are more worried about on behalf of those who haven't than an actual problem for those who are watching the show without having read them. I'm in the latter camp, and the only real problem I had was in the first episode, when it wasn't yet clear which were the five "real" Stark children (since the youngest son is barely shown) and it was difficult to tell Robb, Snow and Theon apart.
That got cleared up pretty quickly, and having recently gone back to watch that episode again, I think a big part of the confusion for me was that Robb and Snow shave midway through the episode and both look different than they did in their first scenes. With hindsight, they actually do a solid job pointing out where Snow and Theon fit into the thing, other than spelling out exactly why Theon is there (something they've done so much in the last few episodes that it's hard to assume anything other than that he's going to screw the Winterfell group over at some point).
Late to the party and it actually took some time to get into (trying to keep track of who is related to who) but I'm on board.
We only got to discuss this briefly in the chat, but I'm curious, what's your top ten rankings on who could beat everybody so far? The Mountain and Drogo should have the top spots locked up, but things get muddy for me after that, thanks to Jamie and Ned going to a draw and The Hound losing to The Mountain due to ref stoppage in the jousting episode. Bronn (the guy who championed Tyrion) and The Knight of Flowers would take my #6 and #7 spots. I'd probably fill out my Top 10 with the old bald guy in the King's Guard, the guy with the whip in Drogo's camp and Jon Snow at #10, who would be like one of those guys who win a season of The Ultimate Fighter.