Here's one question I'm still asking: What exactly do they have in receiver Jerome Simpson?
Jerome Simpson has impressed the Vikings with his willingness to learn, not just his talent.
Even an amateur's eye can see that Simpson's size (6-foot-2) and ball skills separate him from the rest of the team's receivers. We know he can jump over defensive backs (literally), and it's easy to envision Ponder targeting Simpson both on crossing routes and down the sideline.
But even if you assume Simpson has set aside the personal problems that led to a 15-day jail term this spring, it's only fair to note he has played one full season since joining the Cincinnati Bengals in 2008. Most of his 71 career receptions came last season, and he is far from a finished product.
If nothing else, however, three days at the Vikings' camp revealed Simpson making a genuine and inspired attempt to earn the trust of Ponder and the rest of his teammates.
"Really, all I want to do is get comfortable with this offense and get on the same page with Christian," he said. "Every day I'm just basically talking it through with him to understand how he reads everything."
Simpson appears also to have tapped into the competitive side of Harvin, who carries the unofficial title of the Vikings' No. 1 receiver.
"It's been great to have Jerome here and I think he's pushing Percy a little bit," Ponder said. "I think Percy has gotten a little better, and it's almost like a competition to see who is a better receiver right now. I love seeing their relationship. The have a great relationship with each other. They're hanging out off the field together and they both look good. They're getting me excited."
Said Simpson: "Percy is one of my best buds. He's helped me out a lot, just helping me understand the offense and the terminology and everything. We're able to talk about anything."
So how big of a role will Simpson play in the Vikings' offense once he returns from a three-game NFL suspension? An important clue has come during training camp, where the Vikings have used Simpson extensively with Harvin on their first-team offense rather than giving repetitions to the players who will take his place during the suspension.
"He's one of those guys who plays lights-out in practice, diving for balls, making the hard catches," coach Leslie Frazier said.
Much could change between now and Week 4, when Simpson will be eligible to play in the regular season. The Vikings didn't commit much by signing him to a one-year contract worth $2 million, but expectations are beginning to rise.