Victorino probably isn't going to be much more than a bench bat for the Angels, probably to platoon with current Angels' left fielder Matt Joyce. It's good for him, though, as the Sox have had the hot Alejandro De Aza playing right field lately, and the Sox needed to make room for Rusney Castillo, who's been stuck at AAA Pawtucket for most of the season. Shane gets to go to a contender rather than be mired in last place.
The Sox receive only minimal salary relief, but really, what they were really after was Rutledge. While the infielder had a nice offensive showing in 2012 with the Rockies, he's a bat-first player. He's a career -11 DRS second baseman and -20 DRS shortstop. Perhaps the Sox are hoping they can fix his defensive woes; they did it with Xander Bogaerts, after all. If Rutledge becomes just passable on defense, he could be a very useful player. While Rutledge is arbitration eligible after this season, it's doubtful he'll get much of a raise his first time through as he's spent the 2015 season so far in AAA. To his credit, he's performed fairly (.727 OPS).
Really, what this comes down to is the Sox getting future value while giving up a short-term asset. Rutledge probably would have been a non-tender candidate for the Angels this off-season anyway. This way, the Sox can see if he can live up to his offensive potential while helping him to be a better infielder. There's really nothing to lose on either end of this deal.
Will Rutledge be more Brock Holt (utility all-star) or Jonathan Herrera (replacement level disappointment)? Maybe he'll be something in between, but he's worth the shot. Victorino can still play some defense, although he's not what he was, but he's better than what they've had. The Angels needed outfield depth, and Victorino was the most obvious and cheapest upgrade.