Snake's been waiting four long years for the closure he really needs; not an end to war, seeing Meryl grow up, or even his own death can give him what he desires most. What he needs is a trophy. Cold hard platinum in his old hands.
Finally, this month, a patch is coming to Metal Gear Solid 4 that will add trophies and full data installation (as opposed to the disc-by-disc installation used previously). The patch hits Japan specifically on August 6th, while it's coming to America sometime this month according to Metal Gear Solid producer Yoshikazu Matsuhana on the Sony PlayStation Blog.