The Vikings, as I said before, had three major holes to fill this offseason.
#1: a number 1 WR. They traded Troy Williamson, which is as close to the definition of addition by subtraction as you can get. Then they went and signed Benard Berrian. While I don't know if he really is a #1 guy, and they did overpay for him, he was the best WR on the FA market, and the Vikes absolutely needed a WR. You're not going to get a #1 WR in the draft, at least not in that player's rookie season, so the Vikes options were real limited.
#2: a pass rushing DE. With James' injury history and Udeze illness, they needed someone. They got a 26 year old entering his 5th season who has 43 sacks in his previous 4 seasons. When you put him next to the Williams Wall, that is a scary defensive line. With all of the FA DE signing deals before they visited Minnesota, this was the best move available.
#3: a starting FS: The Vikings had a number of safeties leave this offseason, and their depth was very thin. They got Madieu Williams, a free safety who is very good in pass coverage. That is exactly what they needed to play opposite of Sharper.
Those are holes that the Vikings had to fill. If they didn't find something before the draft, they would have to consider that during the draft, and drafting for need instead of drafting best player available is a recipe for disaster. I don't consider that buying a championship, I consider that filling your holes so that you can build through the draft. They just happened to fill the holes in their roster with expensive players.
The last two years, since the current staff has been in place, they have drafted 14 players. Ten of them are still on the team and have shown great ability and/or potential. That is a good job of building through the draft. The Vikings still have 6 picks this year (though mostly in later rounds). That still gives them a good chance to find players who can be a part of the future of this team, especially considering this staff's demostrated abilities in the draft. This deal doesn't affect future draft classes.
I don't think the Vikings have mortgaged the future, or that they're turning into the Redskins. The Redskins MO was to overpay for fading stars. The Vikings MO has been to overpay (hey, it's free agency) for young potential stars coming off of their first contract; guys that can be with the team a while.
We'll see how the draft pans out, but I think this is going to be a great move for the Vikings. Finally being able to put some pressure on the QB should allow the pass defense to get its head above water, and paired with the #1 rush defense (for two years running), should put the overall D well into the top 10.
The success or failure of the Vikings' season now rests on the improvement (or lack thereof) of Tarvaris Jackson.