you can display both, but in my experience adsense works much better. Unless you have very targetted traffic, don't expect to make much from CJ. I have about 2 million pageviews a month on one of my sites. This translates into: - $3500 in Adsense - $5 in CJ - $9 in Amazon affiliate programme. In my opinion, if you use your time getting more traffic, it will be more rewarding