I tried out Tailoring (cloth armour) during the last Beta weekend and although I only got to around Lv.50, the early indications looked very promising.
My crafted armour was not only marginally better than the equivalent vendor armour, but each armour piece looked to have a variety of possible recipes, allowing me to (with the right ingredients) deliberately create armour pieces focused on very specific stats. I even discovered a recipe for creating a unique type of bag. Assuming the other crafting professions follow suit, this looks to make crafters exceptionally useful for catering to your exact needs (by contrast though, with so many specific recipes, it might prove challenging guessing the right stats for good sales in the auctionhouse).
The thing I like most about what I saw of GW2 crafting is that it has the potential to be really co-operative. Gone will be the issues of players competing for resources. Harvesting a node didn’t remove it for other players – we could potentially have a hundred players harvest the same node (must screenshot if we ever do). Mobs were much the same – I saw multiple players claiming loot from the same downed mob, so everyone who got a hit in had decent chance of a beneficial drop (potentially useful for teams of players co-operating to farm mobs for specific ingredients).