Nice, which will make the game even bigger when Elona and Cantha expansion comes out... wow..

It's.. p1f2p I guess.. Pay once, free to play.

The spotlight video by yogscast is quite nice, get to see a lot of skill. So far Necromancer,Engineer,Mesmer, Thief and Guardian.

Guardian " Banish " skill is very cool.

They're separate continents. Both Cantha and Elona won't be available at the start of GW2 due to lore-related reasons. You need to play GW:Beyond to understand some stuff, like Gwen+Keiran Thackery's heir.
The answer is all over the net. Look for it please. 

Guild Wars 2 FAQ (Most of your questions asked like izzit F2P, etc. can be found here, just a few clicks away)

http://www.guildwars2.com/en/the-game/game-faq/

Guld Wars 2 Press Beta Preview Articles and Videos Compilation (Details like WvW, PvP, Dynamic Events, Personal Story, etc. and reviewers opinions can be found here)

http://www.guildwars2journal.com/_/news/gu...ompilation-r106

Enjoy