[My post in the original Guild Wars 2 thread got buried in less than an hour. This seems worthwhile as its own thread, though, with BWE3 and launch coming up very soon. Adding a few extra tips here as well.]
A few bits of useful information for any newcomers:
1 — Much like when you started in FFXI, don't make the mistake of not using the "Auction House" (Trading Post). Don't vendor/NPC your drops.
2 — Start on a craft ASAP. 8-12 slot bags of various types are a gold mine currently (lol). That won't last, but there will obviously be other in-demand items to be made.
3 — The very best way to gain experience points, if playing solely in PVE, is your personal story. A close second is roaming the map completing Renown Hearts and stopping to take part in any Dynamic Events and Skill Challenges along the way. This will also lead to bonus XP and items for complete exploration of an area (which also requires finding all of an area's waypoints and points of interest).
4 — Once you've reached level 10, pick up some harvesting tools. Sickles for gathering plants, hatchets for harvesting lumber and, of course, pickaxes for mining. This should all sound very familiar.
5 — Don't neglect your other weapon set! If you aren't weapon-swapping in combat, you're not using all 15 of your available skills. Whenever 3 or more of your current weapon set's skills are on cooldown (especially if it's a long cooldown), switch to your other weapon set.
6 — Dodge, dodge, dodge! Enemies in Guild Wars 2 telegraph their most powerful attacks. If you see something charging up, get the hell out of there!
7 — Use those defensive abilities! Don't just stand still in the background with a ranged weapon pressing '1'. You have at least 15 skills available (and far more if you're an Engineer or Elementalist) and there's a good chance you have various block/evade skills you can use. In order to gain the attention of a standard enemy (those not labelled "Unpredictable"), all you have to do is be the closest player to that enemy. Once you have its attention, burn those defensive skills and dodge back out of there to let another player use theirs.
8 — Finally, whenever it's time to pick up some new equipment, once again, don't neglect the Trading Post. Most players will post what they believe to be valuable or useful for very reasonable prices, I've found. I had a pretty impressive set on my level 37 Mesmer by the time the last stress test ended.
Should about wrap it up. Others should post any other helpful tips they might have (I could use a few too, of course). See you in-game, BG.