All the rumors. All the theories people had. The letter placement. The space WITHIN the letters. It is all true. The Phantom Pain is Metal Gear Solid V.
In a 5-minute trailer revealed today during GDC, The Phantom Pain was finally confirmed as being a part of Metal Gear Solid V. Kojima also stated that Metal Gear Solid: Ground Zeroes is Metal Gear Solid V as well.
"Ground Zeroes" is a prologue of "MGSV". Kojima said on TwitLonger. "9 years after that event will be "The Phantom Pain". MGSV is constructed w/ prologue and main game "TPP". The game play demo I presented today is the opening of "TPP" which is tutorial that starts from crawling."