Week 4 of the NFL season gave football fans plenty to talk about, with the return of the regular NFL officials, and perhaps...the Minnesota Vikings?

After a huge Week 3 win over the dominant San Francisco 49ers, the Vikings brought their momentum into NFC North play and completely shut down Matthew Stafford and the Detroit Lions.
So what's the secret to the Vikings' early-season success? And will this team continue to pull off victories like these as they get into the meat of their schedules?
Watch the video above to see what NFL lead writer Matt Miller has to say about Christian Ponder and company, and make sure to sound off with your own most-improved teams for Week 4 in the comments section below!