New Mobil-1 product?

I was at Wal-Mart the other day buying a 5-quart jug of Mobil-1 5W-30 when I
noticed that they now had two different 5W-30 products in stock - one had
the normal blue cap, and other other had a grey cap. The product
description on the back of both containers was different - not sure if it
was just a packaging change, or a change in the product itself.
I checked the Mobil-1 website, but they didn't show anything about a change
in the forumulation. I remember over the past few years there has been
several formulation changes such as the move to tri-synthetic and more
recently SuperSyn. So, anyone know what changes were made this time?
Thanks.