The Kojima teaser site, which is rumored to be for the next Metal Gear Solid game which stars Raiden, has recently been updated to have lightning, a countdown, and a flashing 5. It has now been discovered that when the lightning flashes on the screen the date "April 2007" can clearly be seen at the bottom of the screen. Take a look in this screenshot.
It seems as though the April 2007 date means nothing. The Kojima teaser site actually used the boarder from a poster of the movie "Grindhouse". Whomever put it together forgot to clean up down there. The Dimension Films and Troublemaker logos can clearly be seen to the left and right of the date. There is no confirmation if Kojima gained the rights to use this for the website. The poster can be seen at the following address.
The Kojima Teaser Site has since been updated, and the April 2007 date and any other writing from the "Grindhouse" poster is now gone. They must have photoshopped it out. The new picture can be seen here.