Spent the day at Scarefest yesterday - and although it was busy, it certainly wasn't unbearable.
The Queue Times crowd calendar had predicted 89% capacity, but in reality it was only around 65%. So there were definitely queues for things, but nothing over 75 min all day, as far as I could see.
We had platinum fast track though, which was 100% worth the money. Another couple was telling us at the start of the day that the park had sold out of platinum (they'd wanted to buy them but didn't buy in time) - so I was expecting to have to stand around in lots of fast track queues. But I needn't have worried, most fast track queues were five or ten minutes. I understand the aggravation some people have with fast track; but as this was my only visit of the year, and my first time, I'm glad that we paid the extra. Untill Merlin introduce a more egalitarian fast track system (like Disney's timed slots), then I'd probably get it again. We managed to get 22 rides in yesterday, which isn't bad considering we didn't get on park and ready to go untill noon.
Good to see lots of people in the Halloween spirit and dressed up! The decorations around Towers Street were great also.
For a first time visit, I don't think it could have been a better experience. Thanks to everyone here for all the tips and tricks!