Skate 3 has a skate park editor and it is the most impressive one I have ever come across. I actually found the campaign a lot of fun and think they did a great job. Some of the challenges in the campaign can be really hard and sometimes very frustrating, but there is a difficulty slider than you can use if you find yourself getting frustrated. I found the AI to be pretty good in this mode and it was like they were as good as you are. What makes the challenges in Skate 3 stand out is that some of them require you to skate at the same time as your teammates. You do this by working together and completing different challenges. The idea of the campaign is to form an elite team of skaters. Do not worry though as this is still a fun experience if you are playing on your own which is what I did. The campaign of Skate 3 was designed with online play in mind. I am a huge Jason Lee fan and thought that his performance was excellent and I am sure if you are new to the series you will find his tips very helpful. One thing that I got a real kick out of was how they have Jason Lee playing Coach Frank to teach you the basics. Instead, they have spent the development time just refining the game and making it overall better.
That to be fair was a good decision as Skate 2 really nailed the gameplay.
To be brutally honest with you EA did not change a whole load of stuff from Skate 2 with Skate 3.