The switch to B.C.E. and C.E. is also because the year of Jesus' birth is debated. Some believe he was born in 4 C.E. At least that's what I recall from school many many years ago. Personally, I prefer "B.C." and "A.D." because those two are more different from each other (edit distance of two) than "B.C.E." and "C.E." (edit distance of one, unless you count periods).

Edit: Wikipedia says Jesus was born in 5 B.C. (http://en.wikipedia.org/wiki/Jesus)