Brava to Mena for starting a conversation by asking how people are currently using MovableType. Here's my answer.
Here on mamamusings, I actually have one blog, with one author, which you're looking at right now. This site would continue to qualify for a free license.
Misbehaving.net currently runs on TypePad, but we'd been considering a move off of it to a full MT installation because the spam problem has gotten out of control, and because the management of multiple authors there still leaves a lot to be desired--I'd like to be able to let other people in the group have the ability to manage the site without yielding control for all of my TypePad account, for example. We have ten authors on one blog, so that one would probably fall into the personal edition 10/10 category--except for the Google Ads, which bring in all of about $10/month. So right now, it would cost $120. If all the authors kicked in $12, that would probably work out about right. And at $10/head for new authors, we wouldn't break anybody's bank.
On lawley.net, there are two blogs, with two authors; one for my son Lane, and one for his best friend Jackson. My hope was to have a few more family members blogging there. Right now it would fall under personal edition, but I'm not sure it's worth it to me to pay $70 for a tool that the kids use only occasionally.
On a domain that I set up for my kids' elementary school, I had planned to set up blogs for any teacher who wanted one, so that they could use the blogs as tools for communicating with parents, students, each other, and teachers elsewhere. That plan is on hold pending more information about educational pricing. (And that one's complicated because the blogs are strictly for teachers at a K-12 school, but I own the server and am not an employee of the school.) In that scenario, I expect we'd have a handful of teachers to begin, with a few more added each month as they saw what their colleagues were doing. I don't want to have to continually monitor compliance with the license--"do we need another seat today?"--so I really hope there'll be some kind of flat-rate unlimited use license for organizational contexts. If all the teachers (~30) decided to blog, we'd eventually be looking at ~$850 for the site (before discounts), which would probably be paid out of my pocket. I like my kids' school, but I don't have that kind of money to set something up for them.
And finally, on my RIT server, I've got eight weblogs. Five of them are from past classes, and they range from a one-author site (with just me as author) to a two-author site (me and a TA), to a 36-author site (with students having authoring privileges. One of them is the class I'm teaching this quarter. One is a research grant blog that has two authors (myself and Alex Halavais). And one is a blog for my current research project that has four authors (myself, my co-PI, and two student employees). I don't even want to try to figure out what the cost would be under the current licensing, because it's just too confusing.
Also, on all of those sites I regularly set up "test blogs" when I'm doing redesigns, so that I can test the new templates without messing up the production site. I'm going to assume (yes, I know what happens when you assume) that test blogs like that wouldn't be included in any counts. But that I have to even think about that is vexing.
I find this whole conversation very confusing. What does Moveable Type offer that makes it so valuable? I wish someone would clarify this. I got a TypePad account so I could learn something about Moveable Type, but nothing I've seen in TypePad would make me think this is the kind of software people would pay big money for. Aren't there tons of free software projects out there? PostNuke, Slashcode, WordPress, etc? There are so many good pieces of software out there that are free, I'm left struggling to wonder what MT has that makes it so special. Perhaps one of its users could explain this?
Lawrence, for me the value of MT is that (1) it's easy to install and configure, which means that my students can do it in class, (2) it's easy to set up independent weblogs for additional authors on one install (as I do for my kids on my home server, and some of my colleagues on my RIT server), (3) it's got an elegant, functional interface and templating system, and (4) there are a lot of nifty add-ons that I've become quite fond of (third party plugins).
PostNuke, Slashcode, Drupal, etc require significantly more overhead in installing and customizing. WordPress is short on features compred to MT...though it's catching up fast.
And for a lot of users, the real issue is inertia and (as DrunkenBatman has said in his comments and posts elsewhere) sunk costs. When many of us started with MT, it was really the only viable option for hosting your own weblog. Now there are indeed more options, but switching is always a challenge.
And for me, it's all complicated by the fact that I genuinely like and trust the folks at SixApart, and I'm trying to give them the benefit of the doubt on how all this will shake out. I have no problem paying for good software, and encouraging people who develop it to keep doing so. But there has to be sufficient value for me to do that, I'm not yet convinced that the value I'll get for MT3 is worth the price.