It looks nice and has a stimulating design. If the colors go with the gray walls, I think it would be a good choice.

What's the flooring in the room like?

The floors are wide plank pine with a walnut stain.

I'm looking for something comtmeporary and fun. Any other suggestions? What do others have in their playrooms?

I used Flor carpet tiles in a kids play area in a commercial setting. I ordered extras and could then have the individual tiles washed or replaced as needed. They held up well and the selection is fun.
The rug you are looking at is nice too!

Here is a link that might be useful: Flor carpet tiles

I had a rug in my son's room but tossed it so he could run his cars across the hardwood floors and they would actually roll. The bare floors also make it easier for legos to stand up on. Will your son have a good size area with the rug to still play on the bare floor?