When I moved to Washington almost 7 years ago, my perception of "beach" was based on a life lived on the Atlantic Ocean and Gulf of Mexico. Florida has beaches of white sand and warm, clear water, and it is HOT! You have to coat yourself with sunscreen and try not to bake to a crisp. The sand burns your toes, and every time you swim out into the waves (at least if you're paranoid like me), there's the curiosity lurking at the edges of your thoughts about what exactly is swimming alongside of you. A day rolling in the waves and blistering on the sand leaves you completely spent, craving rest and hydration. Georgia does have some beaches that are a little more "natural" (brown sand rather than blinding white, slightly murkier water), but they are still sand and marsh with bugs, humidity, and heat.
The Pacific Ocean is a whole other creature. It is dark, and cooooold. You don't necessarily wear your swimsuit here, unless you're a brave kid or it's one of the 4 or 5 days of the year that are almost warm enough. There are no real sharks to speak of, at least not up in our neck of the woods. And these beaches are BEAUTIFUL. Don't get me wrong, the east coast has its perks, but you can literally look around and see the evolution of our planet along the Washington coast. When you walk along the waves, you walk on smooth beautiful rocks or dark sand. There are fascinating sea creatures clinging to the rocks in tidal pools along the shore at low tide. There are towering trees housing a multitude of birds, including the impressive bald eagle. The most visible difference on the west coast is the sight of enormous rocks along the beach and out in the water. And by rocks, I mean gigantic things on which trees grow and you could climb if they weren't basalt and might crumble beneath you at an inopportune moment. Yes, you have to wear the Washington uniform - bundle your top up in fleece or other warm hoodie, but wear shorts and sturdy waterproof shoes for climbing and exploring the tide pools - but you want to be prepared so you don't miss anything!
I would be hard pressed to choose my favorite. Both coasts have a lot to offer, but I lean toward my new home, especially after a day at a place as magical as Rialto Beach, and watching bald eagles swarm around me at La Push.