hi,
primarily there using gussian blur ... filter>blur>gussian blur... and just apply it to the layer... also you may want to play with the blending modes....
a l ittle tip that works most of the time,,,, to quickly go thru the various blending modes, i hate choosing one at a time to see how it looks, click on the blending box and then use your arrow keys , to cycle thru, to go up and down......
there a lot of tutorials on this effect... and you should have found a ton of them although most will be very similar....
http://search.aol.com/aol/search?s_it=t ... oft+effect you may take note the search phrase i use....