I have three calendars in my life. Two at home and one at work, and each one announces the beginning of summer differently.
The one hanging over my desk with an adorable kitten meowing at me announces summer on June 21, 2008 with the words: Summer Begins.
My calendar of Light Houses hanging in my bedroom says on June 20th: First Day of Summer.
The one at work from the World Wildlife Fund claims June 20th to be the first day of summer with a simple: Summer.
In New England the start of summer is celebrated with balmy breezes, cookouts, trips to the beach and bug spray.
In Florida summer is tolerated with adjustments to the air conditioner to kick it into overdrive, and a concerned eye on the tropics.
I completely get the whole snowbird concept -- live in the north in the summer, the south in the winter. :)
For me, it's always been a time of enjoying the longer days and warm nights. Whether I'm on the west coast of Florida watching the pelicans and dolphins, or strolling the sandy beaches of Cape Cod, I love the summer solstice.