By looking at all the info given in the manga, I think 'Will of D' is related to the lost history/Void Century.
Maybe the kingdom which was destroyed by World Government(alliance by 20 kings) was ruled by a 'D' initial. And the world government tried to erase the prove of its existence by hiding it. But it was recorded in the Poneglyph which are scattered.
And maybe all 'D' owners are the people who escaped from the destruction.
The people with the D who were dying stated that they might be dying;but their bloodline with the will of D will never die.
And the 'Will of D' is something like that one day a person with the middle initial 'D' come and challenge the world and take revenge for what happened during void century.

[img]http://media.tumblr.com/e43f35cfdd762cc666571a6dd0f163d5/tumblr_inline_mhbel8Cy8V1qz4rgp.gif[/img]

Dude! I was thinking almost the same exact thing! It makes me even more anxious to find out what it really means.

[img]http://www.nodiatis.com/pub/23.jpg[/img]

There has been a lot of speculation like those, mine is that the D are the descendants of the civilization that existed in the void century/lost history. The will of D in my humble opinion is just a certain feature of the D people, from what i can guess its related to freedom or something alike since every D that has been mentioned all tried to live their lives free and have a fulfilling life.

I hardly think Oda will reveal anything about 'Will of D' or Void century anytime soon. He is going to save it for the end and if I am not wrong One Piece will last atleast 10 more years....
Damn you Oda saving the best for the last....

[img]http://media.tumblr.com/e43f35cfdd762cc666571a6dd0f163d5/tumblr_inline_mhbel8Cy8V1qz4rgp.gif[/img]

Hey at least hes giving out great chapters in the meantime! 🙂

wasn't it mentioned somewhere that the name of the destroyed country started with a D ?

and I don't think the will of D equals having a D in the name. It would probably only apply to ruffy as his features seem to be reocurring through time. goldroger was described like him and hundreds of years earlier joyboy who came to fishman island.
I mean joyboy could easily be ruffy's nickname

[img]http://www.nodiatis.com/pub/19.jpg[/img]
[img]http://www.dragonflycave.com/wpay/alakazam.gif[/img]

I mean joyboy could easily be ruffy's nickname

I am also thinking the same. It also means that Mermaid Princess and Noa Ship will make an big appearance in the late future.

Hey at least hes giving out great chapters in the meantime!  🙂

Yea,I guess its better not to be gready.

[img]http://media.tumblr.com/e43f35cfdd762cc666571a6dd0f163d5/tumblr_inline_mhbel8Cy8V1qz4rgp.gif[/img]