I find most people who dont like it tend to be no good at it, and that's usually because of the sheer size of the circuit, there's a lot to learn, then even more to learn to be fast, whereas the average 5km circuit can be learnt quickly then improved upon faster, I found it really hard to learn but GT5, as well as Pcars offer the opportunity to learn the track in segments, that's what I found best, I've been lapping the Nurburgring regularly for the last 5 years across GT5/6 and now pcars, I can get around the track comfortably fast without falling off, though I'm still no where near what the optimum pace is, but still every year the online N24 comes along and I find that I've found another second or two it makes it feel worth while,
One of the biggest selling points for me with this game was the fact that some of the tracks we haven't seen at all or for a while in a game were coming, Cadwell Park, Road America, Macau just to name a few, and I'm sad there isn't more street tracks,
I cant say that I hate a circuit specially for any real reason, other then I hate them because I am bored of them, Silverstone, Monza, Laguna Seca and dare I say Bathurst and Spa Francorchamps seem to be basic staples in all racing games, they aren't bad circuits by no means and I certainly wouldn't want to lose them from any roster but c'mon guys there are so many other great circuits that range from international tracks like Abu Dhabi, Misano, Zandvoort, to national and club tracks like Croft, Winton and Portland that kinda always get overlooked,
EDIT: I hate Willow Springs, thats a yawn fest and a half....