For all you US residents; I'm considering a few things I personally prefer, weather, transit, scenery... i LOVE visiting the east coast and find it super awesome but my heart is on the west coast always.
Tell me why your coast is best
I have in-laws in California and clients in the Seattle area, and have had business travel in the past to places like Marin county and San Diego. But I have never spent more than a month out that way at a time. However I lived in the Phoenix area for 13 years. Doesn't count as Left Coast though.
I am presently about 4 hours drive from NYC and about 200 miles inland so maybe that doesn't qualify as East "coast" but I find the stereotype of the rude, irascible, harried New Yorker to be rather overblown outside the City. The most I can say after living here for 6 years is that people honk their horn at you a bit more than in the Chicago area where I spent much of my formative years, and where I lived just prior to this. Honestly there's not even much of an accent difference in upstate NY from the Midwest; it's only the occasional person hailing from the City itself or places like Boston or points north into New England who exhibit a strong East Coast accent (to my ears anyway).
At any rate the air is clean compared to the Chicago area and the winters a bit milder if you're outside the lake effect snow belt, as we are. Property taxes are obscene but otherwise the cost of living is comparable to the Midwest, unlike California where I'd pay twice as much for half the house (when I lived in Arizona I constantly met people who sold a $2 million home in California, bought a nicer $800K home in Arizona, pocketed the difference and laughed all the way to the bank).
My wife grew up in California and considers it "broken" as a place to live, largely due to cost of living. She'd like to move there to be closer to relatives as she ages, and I can think of worse fates; if you can dodge the wildfires and mudslides and earthquakes it's a beautiful place with relatively mild weather. But if we did it, we'd have to take a big step down in quality of housing. And judging from what I saw this spring of wine country outside of SF, we'd have to live with a lot more bustle and congestion than I'm used to, despite being on the "east coast".
I hate the bible belt, but I've only ever been to Florida when it comes to the coasts, so I can't give an answer based on experiences. I don't like snow, and the east coast sees a lot of it, but I like rain, which the east coast also sees a lot of. I like acting potential, so the west coast would be more viable for that, but I don't like sun or sand.
Lake Erie give Cleveland a NORTH Coast. We have a little bit of almost everything that everyone else has, but with affordable cost of living and no sharks, alligators, hurricanes, earthquakes and bugs get frozen out for the winter. And, hey, we're the birthplace of Rock and Roll!
I prefer the Pacific ocean to the Atlantic, but I need to visit more locations on both sides (e.g.'s: New England, California wine country) to make an informed opinion. So really I'm a Mid-Atlantic guy (cold winters but not like North Atlantic states or mid-western regions, fewer earthquakes) pending further research.
I like the 4 seasons. Actually, I can do without summer. I'm sure both coasts have their benefits and negatives. I wouldn't want to live in a place where there are huge brush fires every year, or shattering Earthquakes or the threat of it, or mudslides. I'm good in the Northeast.
I like the west coast weather better simply because here in the East we have massive humidity, so in the summer its like having a hot wet blanket wrapped around you at all times, which stinks. But, I like the winter and the cold, so north east is the best fer me....