Led Zeppelin have posted a picture of the number "five" on their Facebook page, immediately sending the six and a half million people who follow them on the popular social media service into a guessing frenzy.

The legendary group posted the message early Saturday morning (Sept. 8), after posting a simple "hello" the day before. If reports from earlier in this week are accurate, this could be the band's way of revealing that they will in fact be releasing a DVD of their 2007 reunion concert at the O2 arena in London. After all, that concert happened five years ago.

Led Zeppelin's first three albums were named only by successive numbers, and their fourth is often commonly referred to as 'IV,' but it seems highly unlikely the surviving members of the group -- Robert Plant, Jimmy Page and John Paul Jones -- would reunite for a new studio album at this time. Plant is reportedly in various states of production on albums with two different solo groups -- the Band of Joy and the Sensational Shape Shifters.

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