Importance of the number 7 and X777 in FT

[RaveDragon]

Me and a friend of mine found this rather amusing how everything revolves around the number 7 in this manga.

The dragons vanished on the date 7/7/777
http://www.mangareader.net/135-7181-12/fairy-tail/chapter-66.html

Layla Heartphilia died in the year 777
http://www.mangareader.net/135-7183-15/fairy-tail/chapter-68.html

The above events took place (784-777= tada 7!) you guessed right 7 years in the past.
Its currently X784 in the story line ^^

The 7 kin of Purgatory (this is actually of minor importance but the 7 came up again haha)

This is one I'm not sure of but the year on the newspaper if you squint appears to be a x791 meaning 7 years in the future
http://www.mangareader.net/fairy-tail/234/19
However it can be a X793 or X777 or X773 etc

Thoughts?

[Darjaille]

http://img803.imageshack.us/img803/9755/natusa.jpg
:D
It isn't a coincidence, that makes the mystery more magical I think. We've all thought about what it is and for me, every (if not nosense) theory has its point, so I'm really curious about it. Anyway, the point that Layla had something with Dragons is the clue I believe is true. My bet is she sealed Dragons or helped them go into hiding and then died/disappeared.
I think more info will be revealed the moment Zeref appears on the battlefield.