I love a good city builder. I've been enjoying a lot of Tropico 4 for the joy of stuffing buildings down and then keeping people happy/unhappy. I've been voted out and even had riots. All good fun. I like to tinker.
I found the latest SimCity thrilling to watch up to release but since have been disappointed by all the videos I've watched. I'm not bothered about always online but I don't like being forced to have my city integrated into some sort of network to do well. They're also not that big. I also don't like giving money to companies who treat their users like slaves.
Cities:Skylines looks like the SimCity that SimCity should have been. I agree with RPS that it's not exactly groundbreaking but modernised. I think that's OK. In the same way Torchlight 2 has done the ARPG so very well, I think there was a gap in the market to do city building very well - filling many of the promises that SimCity failed to deliver.
I'm waiting on a sale. My saving for FPV quadcopter fund is eating all my monthly savings right now!