Right now I dont really have much of a choice.
Phase autofocus (AF) is why DSLRs are faster than other types of cameras. This form of passive autofocus allows to know instantly into which direction the focus has to be changed in order to improve. Only DSLRs have enough room to implement a Phase AF, and since it only works when using the viewfinder and not in lifeview, I try to use the viewfinder almost always.
Contrast AF works on the sensor itself. Unlike Phase AF, it also doesnt need any calibrating. However, it doesnt know the direction - it can only start running into one direction, detecting if its right, and if it isnt, switch back. Contrast AF is what all non-DSLRs use.
I remember reading somewhere that there are plans to include Phase AF on fotosensors. This would be extremely awesome. Not only could one have a virtually unlimited number of DSLR quality autofocus points, but also all other types of cameras could have the exact same Phase AF that have been previously exclusive for DSLRs.
This and new electronic viewfinders (EVF) with higher resolutions could create a new generation of EVIL (electric viewfinder, interchangeable lens) cameras that would dethrone the DSLRs for real.