http://faq.gardenweb.com/discussions/2765911/how-do-i-care-for-my-aloe-vera-plant "Many aloes produce 'pups'. When the pup is fully formed, detach it from the mother plant, let it callus over for a few days in a cool, dry area, and pot it up. If it has roots, pot as you would a regular aloe, allowing for the fact that it is smaller and should be in a suitably sized pot for its size. If it has no roots, let it callus over, place the cut/broken end ON the soil, and support it with top dressing. DO NOT WATER IT-it has no roots, so watering the soil will likely cause rot. Instead, mist it every few days. Roots should start forming within a month. When growth is evident, it can be watered."

Most the aloes I get barerooted have a lot of 'useless' roots that die during the traveling process, but I have never ordered an aloe that large. Still, never had a problem with any of them rerooting so my guess is you will be OK. Cut off dead stuff and dip in roottone, and put in pumice for a week or so (or, if you braver, dry cactus soil with pumice in it), and recheck every 5-7 days for signs of new root production. ONce you see that, you can water gently. This is a super fast growing aloe, so with luck, it should crank out some roots soon.

You know, the more I find images of gasteria, the more I feel lied to by the plant tag that came with it. I think you might be right, it is probably not an aloe at all. (I feel kind of stupid now). Here is the "mother" plant the leaf came off of. Even if it isn't an species of aloe - what would be the next step of propagation I should see? Leaves coming up out of the soil, eventually?

That sounds like an excellent plan. Yes, and rocks are your friend there, but then again, the stem's eminently ready for being somewhat tightly staked, isn't it? There may be some truth to the folk wisdom concerning pronouncing 'plicatilis' in a Donald Duck voice aiding the rooting process. If I may be so forward, can you spare a cutting for a brother? I'll be in AZ in December and would pay shipping costs gladly. I'd love to grow this one again.