From Cot's Baseball Contracts:
09:$2M, 10:$4.5M, 11:$6.5M, 12:$10.65M club option ($1.25M buyout)
So the Pirates gave up an inexpensive player who is also considered one of their best players. The prospects are being reported as the following by the Pittsburgh Post Gazette with quotes from Pittsburgh General Manager Neal Huntington:
On trading McLouth: "This may be the toughest decision we have made in my time with the organization. Nate is a quality player and person but, as we have said several times, tough decisions will need to be made as we build and sustain a championship-caliber organization. Nate has worked as hard as any player to become a starting major league Player, proving wrong anyone who may have doubted him. When we signed Nate to a long-term contract, we did so with the intent on having him remain part of our core of homegrown talent. But the quality and quantity of talent we are receiving in this trade moves us closer to our goal of building that sustainable championship-caliber club and compelled us to move a very good player and an outstanding young man."
On Locke: "An intriguing young left-handed starter with the frame, athleticism and stuff to become a quality major-league starting pitcher."
On Morton: "A power right-handed starting pitcher who is excelling at Class AAA. He is close to being ready for the big leagues and has the upside to become a quality major league starting pitcher."
On Hernandez: "A dynamic player who has the potential to become an above-average major league outfielder. He is a quality athlete with plus speed and plays above-average defense. He has bat speed and the upside to develop into a productive table setter."
The Pirates have called up their number one prospect, Andrew McCutchen. He will start in center field. This may be one of the underlying reasons that the Pirates made this trade. Perhaps they believed that McClouth would have a problem with moving out of center field.
I'll have a more complete report on all the prospects involved a bit later.