I've always wanted to get my cats a cat tree but I always worry about spending all that money and then they wouldn't play on it. I shouldn't have worried about that at all!
They were playing on it before I could even get it put together! They knew, as soon as I opened the box that it was something for them.
It was very easy to put together. It only took about 20 minutes and it probably would have went faster than that if the cats would have left it alone. I was really happy with the way it looks, I was expecting it to be ugly and the carpet on it to be cheap looking, but its not at all. 
Its been about a month since I got it and in that month it has had at least one cat on it every second of every day!
I really recommend this if you are shopping for a cat tree. All six of my cats and I love it!