Hernandez helps the Dodgers with pitching depth, as they've had issues with health (Josh Beckett) and effectiveness (Dan Haren) at the back end of their rotation this year.
The two players to be named later for the Phillies are, well, most likely never going amount to much, but you never know! Hernandez was a one-year signing, and presumably the Phillies will receive players they will control for longer than that. So any way you slice it, this is a good gamble for the Phillies to take, with no downside and all upside (though obviously not very likely).
(Although, if all they get back is cash, then it's less so and just a nice thing to do for Hernandez, since he now plays for a contender.)
So far this year, Hernandez has been exactly what he was at the point of being signed - a replacement-level player. He was a freely available talent at the end of the off-season, so almost by definition he was replacement level. And that's what he's done this year, posting a 0.0 fWAR.
As players of that level do, he's shown signs of being really good, but he's also struggled. His 4.62 FIP shows that his 3.87 ERA is a bit deceiving, as does his low-ish .256 BABIP.
Interestingly, Hernandez was supposed to start for the Phillies tonight. With David Buchanan replacing Cliff Lee last night, it's possible we'll see a bullpen-as-starter game tonight, unless someone can make the trip from Lehigh very quickly this afternoon.
More on this as it develops, but in the meantime, let's all say goodbye to our favorite Phillie who used to be named Fausto. Thanks for the replacement-level memories!