Guild Wars 2 has no traditional MMO endgame, but now you can get a summation of the design manifesto straight from the horse's mouth.
ArenaNet Lead Content Designer Mike Zadorojny has authored a blog post called The Endgame Reimagined, and in it he says that yes, Guild Wars 2 seeks to avoid making players grind "through chunks of boring, repetitive content to get to the occasional pockets of fun."
How, specifically, does the game manage it? For starters, it introduces elements typically associated with endgame "at every level and every possible opportunity." Things like large-scale boss fights are commonplace, as are the title's dynamic events that spread across the level range. Once you do get to the actual endgame, ANet says that there's still plenty to do. Read all about it at the official site.