I just bought the game and have been playing a bit this week and am running up against the same thing that happened last time (during beta weekends).
I enjoy the first few levels because the combat is actually fun (for an MMO that is) and it's enjoyable to just swap out weapons and get all your skills learned with the weapons, but then as soon as I learn all the weapon skills I get bored and start a new class.
So, since I've never even made it past 7 and this game has a level 80 cap (keep in mind, I have 4 or 5 level 85s in WoW, so I'm not a stranger to MMO leveling), can anyone tell me what compels you to keep going? I may just be burned out on MMOs, which isn't the fault of GW2.
Do skills get more interesting? I dunno. Just looking for a, "Oh, it totally opens up at level X and starts to feel less grindy and more dynamic; you really do just need to play more!" assurance.
Also, warrior or guardian? =)
I tried thief last night and abhorred it.
There are still the utility skills which depending on your class can provide more playstyles and options. There are traits and most traits only emphasize certain playstyles, but some can offer specialization that can't be done without traits. You then have your elites that unlock at level 30.
Beyond that, there's more to learn about how each skill works for new players than people realize. I just leveled a Guardian to 10 and have been unlocking most of my skills. I still have focus to unlock, but I've been very effective with Guardian and leveling faster than my Engy or Mesmer. I think part of the reason is that I better understand combat now and how to use skills. I run Hammer + anything that creates combo fields to smash my Hammer in. This creates great AOE for me and allows me to play a 'drop aoe field and smash it' sort of playstyle. My Engineer didn't really open up until I got more utility skills and toolbelts. It's still not fully functioning at level 17 due to not being able to reach certain utilities like elixir gun.
On my Mesmer, Sword MH took awhile to effectively learn how to melee weave. It's a melee playstyle that weaves in and out a lot, sort of theif or rogue like. Early on, I would just leap in and Blurred Frenzy and that's it. Now I drop Duelist,a ethereal field, leap in to combo finish and immobilize, then stun with the pistol, and either finish with sword hits or shatter. With Feedback, I'm normally sticking that on a range mob and my Duelist on the mob, and then fighting in melee versus another mob with an illusion that I'm shuffling around to see if the mob will hit the illusion instead of me. I might then switch to my other weapon, say a staff, drop a Chaos Storm and iWarlock, have it hit once and see how much life is left. I might pop chaos armor, go back in with sword to finish the ranged mob, let the phantasms kill it, or shatter them to kill it. I can spec my traits to drop confusion in glamour fields and stack confusion on shatters, allowing me to play a glam-trap playstyle, or a power/condition damage playstyle with shatters.
I don't buy into the idea that you've completed your character at early levels. It takes awhile to fully exploit the combat system and figure out how traits work. I didn't start using mantras until last week when I discovered that mantra healing and mantra of pain lets me push out a 2.8k PBAOE heal at lvl 80 every 8 seconds.
edit: All this said, traits are not providing the flavor options they alluded to so long ago. There needs to be less straight vertical traits and more horizontal options. For a Mesmer, the Focus trait that causes focus skills to reflect is a good example of this, as is the Healing Mantra which provides extra functionalities to a set of skills. If you notice, a lot of the Mesmer build ideas and builds I talk about in here hover around traits that offer more flavor. Glam-trap is based on traits that cause glamour to cause blindness and confusion, and then another trait that causes your blinds to also apply confusion. This offers more functionality to Glamour skills, while also making things like Scepter #2 another Confusion application. The Sword trait is good, but boring in design, so I don't talk about it much. Same with the Greatsword trait or Phantasm damage increasing traits.