mTurk: Mechanical Turk seems to be a platform in which (probably where Amazon got the idea from - not necessarily the 18th century chess set) users can take part in mechanical tasks.
as a Requester: http://imgur.com/MYKWwoZ In my experience, posting tasks proved to be quite daunting and extremely limiting in terms of the actions your workers can take. Not only that but the User Interface lacks pretty much everything except probably the functional aspect, but which without intuitiveness loses its purpose.
as a Worker: http://imgur.com/jnIlk3l Doing what probably most users would do, after playing around with a couple of image tagging and confirming website links (<0.05$ per HIT), I started looking what this platform can offer. Arranging everything by potential pay, I had to go through literally dozens of pages in hope to find a task that pays decent. After about 20 minutes of scrolling through pages I gave up and went to finish tasks that seemed easy enough to be paid for.
Overall: I guess this platform can and does work; however, going through and finding a task that pays decent and may not need approval, where the objective makes sense and it stays away from subjective bias that may result in the requester “thinking” you have not accomplished his desire makes this platform a torturer in its own right. However, coupled with some smart tools and enough perseverance to go through with repetitive small (but certain) tasks I believe this platform offers a great deal of opportunity to workers in countries suffering from economic inequality.
TaskRabbit: TaskRabbit (at least in London) seems to be a fully developed platform that allows users to apply and offer jobs in the full spectrum of human capability.
After spending 30-45 minutes on my application I have been thanked for applying to become a Tasker however they were unable to move forward with my application at this time :)
But during my application I was required to fill in the fields and I have to say I was impressed by the breadth of fields where one can apply. Their approach was quite simple: select hourly pay, personal pitch and level of expertise (4 levels: complete beginner, did it around the house, part-time and diploma backed expertise). In the latter, I found that the 4 levels were just not enough, having to put my knowledge (outside webdev and data processing) mostly between did it around the home and part-time. In either cases, I ended up feeling like I was either a jack of all trades who learned and did everything around the home or someone that has had too many part-time jobs.
upWork: What I know to be the best fully developed platform that allows users to apply and offer jobs in the creative or developer industry (mostly).
I have only tried it as a freelancer. This is as far as I know the most popular platform for freelancers. I liked creating and profile and with all the skill-evaluation I felt like this is something that can truly reflect one’s level of expertise. However, often you’d have to compromise when focusing on your main abilities as there was only one field of selection. In the end, the profile is very important in terms of matching you to employers based on both skill and personality but one can get lost in all the processes with no real guarantee of finding specific work based on these two. The rating system is one that is understandably good however not flawless. In your Daemo article I think you explain better than I could and I assign this to their incredible no of users (they boast 3 million). This pushes good and probably professional users to inflate ratings in order to maintain (or strive for) better visibility and changes to find work/workers.
MobileWorks: Just like as in the case of the mTurk, I think this platform tackles economic inequality beautifully however as opposed to it, it actually makes sense because of the limiting technologies. Also I believe the article was probably written in 2011, when the mobile technology was just starting to bloom (or at least capacitive screen technology). Nowadays, perhaps a lot more can be done in terms tackling more complex tasks (not necessarily more complicated, perhaps multi-media wise).
Daemo: The 3 studies speak for themselves. I believe Boomerang is probably the most real and very-difficult-to-trick raking/reward system. My main concern was that very good users (and professionals of course) would sweep everything into one’s net however this is difficult to predict and as long as novice users won’t be completely downgraded with one bad rating the most problematic issue is nicely tackled.
FlashTeam: Again, results speak for themselves. The flash teams seemed to require less coordination and managed to finish the work in almost half of the controls which translates into less money required of an employer which could of course translate and fuel a popular platform. However, some success may be credited to an agile-like team build, which I doubt is a coincidence as it would have been the best choice for scalability. One thing I was also intrigued by is the apparent waterfall workflow when tackling the overall project because this allows potential changes at the team level.