So the main difference between it and the first game is "persistent worlds" I guess, unlike the first game where you'd only see other people in towns unless you're in a party GW2 has the classic open worlds that you'll find from regular MMOs, the one difference is that if the map is full you'll be put into a second "spill-over" area in a queue until there's room for you. Sometimes the spill-over map has enough people in it to warrant taking part in various events. You'll get instances just for you (and probably party), much like in FF14, for special quests. Due to having persistent worlds you have to choose your world/server at the start and sadly this seems to stick for all your characters, you have to buy a pass to swap servers.
The really cool thing I like is that they promote exploration. The city maps are gorgeous and expansive and every map has "points of interest" as well as way points and other "hidden" things I forget the name of, getting any of these will reward you with experience and if you complete a map you get a bonus reward of exp and moneys.
Looks like you get 5 character slots to play with, there doesn't seem to be sub-classes or whatever like the first game but I think you are able to swap classes.
I'm on Piken Square ATM, obviously it's an EU server.
Actually was 2 years ago methinks, launch of FF14. Thought it'd be fine but looks like I'll have to upgrade the GFX card as well 
