First of all this should be no surprise. People, consciously or unconsciously, follow the money. Computer science majors were a very hot property in the late 90's and now they are less so. So less people are going into computer science.
My advice: Don't follow the money. You will be trying to time the market four years down the road. I remember as an undergrad seeing many of my fellow freshman going into Chemical Engineering because it was a hot area. Four years later many of them had trouble finding or keeping a job and had to move to other areas. Some of them even became.......lawyers.
Best to do what you enjoy. If you enjoy it you will have a better chance to succeed. Worry about the job market when you get there.