As said before, a BS in Computer Science usually translates to jobs dealing with engineering (Software, Network, Systems, etc.). The courses are generally more difficult then those that make up a CIS degree because of the math and science involved. Those who get CIS degrees usually end up as Network Administrators, Web-Developers, Tech-Support, etc., those that utilize the technology created by the Computer Science guys. The dot-com crash had a large effect on these types of jobs. Though there are still jobs out there for the CIS/IT grad, the market is a little flooded with those whom whom have lost their jobs.
IMO there will always be available jobs for those with a CS degree. There is still a void in the market for software engineers. I graduated a little over a year ago with a BS in Comp Sci, and when I was job hunting, I would receive at least 15 emails and 5 calls a day from companies who were interested. Even now, I still get an email every once in awhile from a company trying to solicite me for a job.