From Wiki....list of current members
3M · Alcoa · American Express · AT&T · Bank of America · Boeing · Caterpillar · Chevron · Citigroup · The Coca-Cola Company · DuPont · ExxonMobil · General Electric · General Motors · Hewlett-Packard · The Home Depot · Intel · IBM · Johnson & Johnson · JPMorgan Chase · Kraft Foods · McDonald’s · Merck & Co. · Microsoft · Pfizer · Procter & Gamble · United Technologies Corporation · Verizon Communications · Wal-Mart · The Walt Disney Company
To me, it would make the index too tech heavy
And it would also make the index an accurate reflection of the current state of American industry. ;)