I'm usually the kind of MMORPG gamer that enjoys the grind. I've actually been enjoying grinding up my Hunter in DAoC: I can meander about and kill monsters and adventure through a short dungeon with the result of getting a level or two. I'm already 40 and I'm only just starting to feel the tedium set in as the last ten levels are, if I recall correctly, much longer than the first forty. Anyhow, I'm not at all feeling the same way about my Chosen in Warhammer Online. He's stuck at 28 (or 29?) and I can barely cleave an elf in twain before I grumble about how this isn't going fast enough.
The problem isn't just the speed of it, it's the methodology of it. Actually, it's a similar problem I had in EQ2: I don't enjoy grinding quests as much as I enjoy grinding kills or dungeons. Quests are irritatingly tedious: it's not enough to do them, you have to puzzle through them, and not in a fun sort of puzzle-solving way. It's more a "decode the esoteric quest hints and map markers" sort of way.
The worst part of questing is how you have to keep going back to turn them in, or when you get several quests in the same area but not at the same time so you have to revisit it. The thing that bugs me about quest grinding is the inefficiency of it all. Killing monsters is efficient: you dispatch one and move on to the next. You don't have to go back to a guard three towns away and click through 10 pages of meaningless dialogue before getting back to the fun part of the game (the "playing it" part).
WAR's Public Quests are a lot of fun, but they just don't generate enough XP to be grind-worthy. I'd love it if you could get to 50 by just doing PQs. Well, enough of this rant, WAR's got enough problems with PVP and population as it is. Not even sure how much the grind affects the population numbers; I'd suspect probably not by much...