CF cards are currently the standard when it comes to DSLRs, only the new Rebel uses SD AFIK. I think that is still partially due to their more robust form factor and because they are usually the first to come out in larger capacities with more throughput. You'll probably see more mfg's switching to SD however.
I personally don't like SD cards, they seem too small and flimsy. I had one of my CF cards go through the washer and dryer in my pants pocket yet it still worked perfectly and had all the files intact I had shot that day.