I'm majoring in computer engineering and I'd say it's pretty awesome. It's more hands on than computer science. CPE majors work on both hardware and software. Almost every device or thing today probably has a chip in it (embedded systems) that need to be designed (hardware) and programmed (software): cars, MP3 players, cellphones, game consoles, etc. CPE is like EE with analog/power stuff removed with more focus on digital systems (hardware logic, FPGAs) and CS with less emphasize on algorithms with more focus on lower level programming combined (assembly language, memory controllers,etc.)
That being said, I don't think CPE is an easy major. You get all the math from EE (calculus, differential equations, etc.) and all the math from CS (linear algebra and discrete mathematics). Plus, for projects you end up spending a lot of time debugging both the hardware and software that you both had to design from scratch. Right now it's my first year in college and we are designing a 16-bit computer and trying to program it.
EDIT: I know that you shouldn't just pick a major just because of the money, but computer engineers on average have a higher salary than mechanical and electrical engineers: http://www.cnbc.com/id/29408064/High...s_2010?slide=7
Either way you can't go wrong between mechanical or computer engineering. They're both pretty important and can make an impact on society and do good things for the world. At least you're not picking a silly major like phrenology or food science.