I can assure you, gw2 will be well worth the wait. If you liked gw but missed everything is wasn't, this is for you =)
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The Game Drone: Guild Wars - The Sequel
Advancement and Combat
Guild Wars 2 will significantly raise the level cap in comparison to the original game. ArenaNet is currently considering a level cap of over 100 or perhaps even no cap at all. The leveling curve will be thoroughly different from Guild Wars however, as the difference between a level 80 and level 100 player will be significantly smaller than the difference between a level 20 and level 40 player. Nothing is set in stone yet - and it is as of yet unknown how this new leveling system will affect PvP.
Further innovations in character advancement stem from a more traditional equipment system. The amount of weapon and armor upgrades (as well as other usable items) has increased dramatically in comparison to the original game - and players can now decide for themselves what kind of armor they want to wear. As such it is perfectly possible to have a mage carrying heavy armor, or a light armored warrior. Additionally - Guild Wars 2 will feature an extensive crafting system involving a revised version of the salvaging system introduced with Guild Wars: Nightfall.
Fortunately - players who have invested hundreds, if not thousands, of hours into their Guild Wars characters should not be afraid of it all being for naught. The upcoming Eye of the North expansion pack for Guild Wars will introduce a personal instance called the Hall of Monuments. This will track your character's progress in the game and set it's accomplishments into stone to be remembered permanently. As such - when you create a Guild Wars 2 character you can opt to bind it to one of your old Guild Wars characters - and receive various unique rewards (such as equipment and companions) depending on it's recorded achievements.
In terms of combat a lot has changed as well. Firstly the skills will be a lot more visual - it should be more apparent when an attack or skill hits an enemy, which should make combat an easier experience for newcomers. Of course the free movement also plays a part in combat, allowing you to dodge about much easier than before. Another alteration to the way in which combat will play out is the removal of a mouse-control scheme, which forces players to utilize their keyboard for movement.