I've worked for Wal-Mart for nearly 5 years now. The logo is the same as it was after the 2008 change. The store I work in just finished a major top-to-bottom remodel (nearly $7 million), and we got new outdoor signage, same logo as before. The vest I wear every day to work still says Walmart on one side of the chest & my name badge still has Walmart with the little "spark" logo next to it written on it.
As others said, when the new Walmart.com site design launched, they chose to use the "spark" as the icon to declutter the home page and put the focus on the merchandise being offered for sale.
I'm not sure where you're getting your information from, but you're sadly mistaken.