It's quite easy. Just squeeze a certain section and push them off. You can see the latch if you look closely. The new ones should slide right on and snap into place.
I believe your car has a latch, as I have a 2002 Impala, and mine has a latch. Here's a little direction for you:
http://wiki.answers.com/Q/How_do_you_change_wiper_blades
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