That thought struck Lisa Degliantoni, an educational fund-raising
executive in Chicago, a few months ago when she was planning her 39th
birthday party. After a move from New York to Evanston, Ill., she
realized that she had 857 Facebook friends and 509 Twitter followers,
but still did not know if she could fill her party’s invitation list. “I
did an inventory of the phases of my life where I’ve managed to make
the most friends, and it was definitely high school and my first job,”
she said.