Before I say anything else, I should clear any assumptions of my motive. Glitch is the most well-designed game I've played all year. It's exceptionally smart and has an impish attention to detail that you usually see in well-written literature, but never in games. I have the rare feeling that I can be proud of a game I play and the community surrounding it, and not like an addict with a dark secret in his closet.
Having said that: with the way Glitch is right now, you can blaze through most of the game in a week, and probably finish everything in two. I've been playing for three days (granted, three days of a lot of free time) and I've already crossed the monotony line -- that point where you're out of "I have so much to do!" land and into grinding for big-ticket status items like houses. Compare this to other MMOs or even certain social games like FarmVille where the bar for reaching "you've done everything" is much, much higher, which is saying a lot since FarmVille is the epitome of a grind.
The monotony line is really, really low in this game. That is, if you think about when you were level 5, or level 8, you could level up simply by going around and doing things. There was so much to do. You had definite goals -- save up to buy a frying pan, for example. Then you're level 12, and there's a little bit less to do. By the time you're level 15, you can't just go around and quest anymore because the quests give a pathetic amount of XP relative to your level. The goals have less significance. You've acquired pretty much every significant tool in the game.
This is roughly the monotony line. It's where you descend into monotony -- your actions have less significance, your progress seems less meaningful, and you're just hoarding resources / grinding. As of right now, there aren't many meaningful quests I can go on or items I can look forward to buying. Quests stopped being useful at around level 15. Items stopped being a big deal at level 10 -- the most expensive item I can think of costs ₡2,500 and you can acquire that pretty early on. Compare that to something like WoW, where you had to work your ass off to get an "epic mount" and the gear you could get scaled well into the highest of levels.
The only big-ticket item that scales into the high levels are the ₡50,000 houses, and even then it scales poorly since one must go through a ridiculous amount of grinding to acquire that many currants. Ideally, you could just continue to do higher-level quests for even higher payouts.
On top of the lack of meaningful quests/items beyond the teens, it's very easy to feel like you've "seen everything" very early on. How many online games can you think of where you've explored almost every area by the 2nd day of play? Level 13 was the point when I had explored most of the world of Glitch, which simply doesn't happen in other online RPGs: there are low-level worlds, and there are high-level worlds. Glitch has no high-level worlds. Axom, who is level 23, is 13th on the "top travellers" leaderboards. This means that someone who has been playing for less than a week can see pretty much every area in the game.
All of this is a problem.
Players do not start buying something like subscriptions or credits until they've played the game for a reasonable amount of time. In League of Legends, for example, I didn't purchase my first instance of "RP" (their equivalent of credits) until I had played for something like 60 hours. I spent money on the game knowing that I had already invested a lot of time into the game and would continue to invest more, so it made my time invested more enjoyable. Why will someone buy credits or a subscription when it's so easy to jump in Glitch and be done with it within a week or two? The time you would buy credits is the time when you've done most of the things to do in the game and have little incentive to keep playing.
Glitch has had millions of dollars invested into it. Clearly, there is some expectation of payback. If there is no incentive to keep playing well into the high levels (30-60), there will be less incentive to buy credits and Glitch itself could suffer as a result.