Just about 90 minutes before the WWDC 2011 keynote is to begin, a Walmart rep just dropped me an email letting me know that they've dropped the price of the iPhone 4 by $50. Starting today through June 30, you can grab an iPhone 4 for $147. This applies to both the AT&T and Verizon models, in both black and white. Of course, this pricing requires a two-year contract. Very interesting, as we aren't expecting any iPhone 5 hardware news this morning at WWDC--does Walmart know something we don't?