My own thoughts on the Vikings are that they really need a quarterback, especially now that Cassel has voided his contract, but I don't really know if one of the big four (Manziel, Bridgewater, Carr, or Bortles) will be there at #8 when the Vikes pick. I think that will depend on what the Texans and the Raiders do -- I personally can't see either of these teams not picking a QB. There can't be any doubt that Cleveland and Jacksonville will take a QB.
If all four are gone by the #8 pick, Minnesota should probably go defense, and see what they can do in the 2nd or 3rd round about a QB (Garoppolo in the 2nd or Mettenburger in the 3rd perhaps).
It's also possible that perhaps Norv can get something out of Ponder, who knows. One things for certain, the Vikes need a QB in some fashion whether it be to back up or just another arm for practice, because right now they only have one.