It's not that white boards are so much better, but chalk dust aggravates my asthma.
Some white boards are magnetic. Comes in real handy for increasing training aid repertoires. I made a magnet-backed cardboard suit of armor for a lesson. I could plop each piece up on the board one at a time and then write labels next to them with the markers. My instructors liked it so much, they asked me to leave it with them as an example for further classes.