First thing I thought of is that its the Intergral/Substance/Subsistence version of MGS4, not a 360 port.
Same.
Though honestly at this point I'd wish they'd release a game set after Portable Ops and before MG1. MPO was billed as the "missing link" between the Big Boss of MGS3 and the Big Boss of MG1, but it just showed how FOX-HOUND got its start and how Big Boss got enough resources to create Outer Heaven.
MGS4 did more to explain that gap in time, and it felt totally phoned-in and undeveloped. But a game set during a period when Big Boss was being used as an international propaganda tool by the Patriots could show their motivations and develop them into their MGS1/2/4 selves. Not just MGS4's half-baked, "oh well they both loved the boss but then some of them turned evil and big boss was angry."