I have two level 70's at the moment, one level 45 who is actively progressing upwards, a level 48 who is parked waiting until my fiancee has enough time to play again, a level 8 priest who may hypothetically progress upwards (though it'll be bad bad news for Blizz if he makes it before the expansion), and plans to at least experiment with a DK. This doesn't make me all that unusual - it seems like most serious players, unless they raid and literally need all of their spare in-game time to deal with upkeep costs, have at least one max level alt. But this raises an interesting question - how do you gear your alts?
I previously discussed the ways in which time spent on your main can help your alts, and Wrath is supposedly adding in a new one, with so-called "Legacy" items that will be bound to your accounts but will allow you to hand them down to your alts. My discussion focused on reputation, accomplishments, and attunements since I was talking primarily about the leveling game. When you get to the level cap, however, the goal of all these activities is getting better gear.
Zereissen has an impressive shopping list to gear one of his several level 70's, and he acknowledges that time is at a premium. He has the advantage of being in a guild that allows alts to raid, and I'm sure that having three or more raid-ready alts is a huge asset to a guild that flexible. It works out because he actually wants to be raiding, and every step, even if it's distributed among several characters, and even if it takes a long time to earn the money between raids, gets the next character closer to that goal.
Unfortunately, that motivation doesn't work for me; I would rather be spending time doing a variety of content, so pigeon-holing myself into the top 10 dailies (on a cash/time basis) every single day is the exact opposite of my goals. The result is that I wind up basically retiring alts. Take my uncrushable solo Pally: I'm happy to spend 100-200 gold on BOE blues, even ones that I'm probably never going to actually use, because that's 1-2 hours of daily quest gold at the most. (Interestingly, the time it takes to farm the gold for a blue ilvl 115 item is not all that different from the time to run an instance with a competent PuG, so maybe Blizzard is better at in-game economics than we thought.) I will not spend 1000 gold on BoE purples, because the magnitude of the gear upgrade I would get is not high enough to justify the amount of time I would have to spend doing the same content over and over again.
Maybe the price is right. I certainly could keep on working on the Pally (or maybe even the mage) if I wanted to, and Zereissen's example (among many others) proves that concept in action. But one could also argue that I would like to keep playing my 70's, that Blizzard would in principle like me to keep playing them too since that's more time I'd be playing WoW. So, in economic terms, we have a buyer and a seller, and it's just a matter of finding a price I'm willing to pay that doesn't undermining other content. I don't claim to have an answer (if I did, I'd be out trying to sell World of PVD-craft ;)), but I wonder if someone will. Maybe the trick is simply to put a significantly larger gulf between the gear you have when you hit 80 and the gear you get when you start raiding or crafting epic gear, so there's more room to grow without stepping on the toes of raid content. Hopefully, Blizzard can figure it out in the next few months.