I have not found any software -- proprietary, open source, or free -- that compares favorably with proprietary Camtasia when it comes to quickly making and editing screen capture videos and, in many cases, live video as well. Worse, Camtasia is available only for Windows (although I've requested a Linux version), so I end up recording a Linux screen on a Windows computer via VNC.
There are free software packages available that, combined, can do most of what Camtasia does, but they run up editing time by a huge factor, to the point where practical, economical production is nearly impossible.
Flash - both great and evil
Camtasia easily converts .avi files (its native output) to Flash. So far, after nearly two years of experimentation, I have not found a file format that gives me file sizes anywhere near as small as .swf (Flash) for Web delivery, especially when I deal with screen capture-type material for which I feel 640X480 is the minimum viable picture size.
But Flash is proprietary, and therefore evil, and there is no Flash plugin available for a small subset of NewsForge readers that use certain free operating systems. I've thought about alternate file formats, and have asked some of the most vocal anti-Flash people for suggestions, but I have gotten no useful input about how to rapidly and easily convert .avi or other video to formats they prefer -- and that can be delivered without special server software of some sort.
I'm still listening, and I'm still willing to accommodate the few readers/viewers who can't (or won't) view .swf files either with the proprietary viewer available from Adobe or through the new GPL Gnash .swf viewer. But for the moment, I see Flash as the easiest-to-produce, lowest-bandwidth method of delivering short videos over the Internet. When something Free that's at least as good comes along, which has players for most popular operating system or (better) requires no client/player at all, I'll jump on it so fast your head will spin.
Many other, similar cases
I use GNU/Linux (currently Ubuntu) for my day-to-day work and Internet activity. I strongly prefer Linux over Windows (and Mac OS X) not only because it's Free Software but also because I find it stable, secure, and easy to use. There is no part of my daily work I can't do with Linux and Free Software -- except video, which currently occupies perhaps 10% of my total working time.
Last night, at a Linux users gathering, I heard how hard it was to lure desktop users from Windows to Linux at some members' workplaces. In most cases their companies are dependent on Windows software that may never be ported to Linux. It was a constant refrain, and one you've probably heard many times yourself: Linux can now do 90% of what everyone needs, but there is still that 10%, and the 10% varies from user to user and from company to company. And even if the applications those companies need are ported to Linux, they will still be proprietary, so the operating system switch won't suddenly, gloriously move them into the Free Software world.
This doesn't mean we should give up hope. GNU/Linux has come a long way from when I first tried it back in 1996 or so. Back then, mounting a CD-ROM and setting up a printer were notable chores. Now, when we review distributions, we don't even mention these tasks; we assume they are no-brainers, only notable if they aren't. And there is Free Software available for all kinds of tasks that could only be handled by proprietary software (or simply weren't doable) only a few years ago.
But right now, and probably for at least several years to come, we must accept the fact that not everyone will be able to do everything they need to do with a computer without resorting to proprietary software -- and all too often, a proprietary operating system -- at least part of the time.