No wonder people are drinking the S&P 500 Kool-Aid, says Jim Cramer on new additions to the index

Last Friday, S&P Dow Jones Indices announced the latest round of changes to the S&P 500 with three new stocks joining the index. And there's nothing more positive for your stock than joining the number one large cap benchmark. So many index funds exist to mirror the S&P 500, meaning they'll all be forced to buy the new additions.You get an instant, sometimes gigantic pop. The additions this time it's Apploven the advertising technology platform, Robin Hood, the iconic retail trading platform, and MCO, which ...