Minnesota was expected to bolster their backfield this off-season so this is not a surprise, and Murray should form a good duo with outstanding-athlete-but-yet-to-prove-it-on-the-field back Jerick McKinnon.
If I'm a Murray owner, I'm happy with this move as it is suggests he will see a decent amount of volume and presumably assume goal-line duties. While the Vikings don't have the most explosive offense, he should be the top option for carries. He's also 'acquirable' for those who don't own him - he was going behind Duke Johnson, Jeremy Hill and Paul Perkins in the February ADP data and will likely continue to be a bargain in startups and no owner should be holding on to him too tight.
Don't overpay, but Murray could flip his 2016 touchdown-dependence to volume-dependence in 2017, and should maintain low RB2 production. McKinnon is still one to watch, but it seems evident the team doesn't view him as a workhorse.