I am working on Microworkers sines 7- February 2010. I was not a regular worker of Microworkers.com as I was not able to submit the high paid job. You may see that above 0.50$ jobs are all website based and all needs a website with Google Page Rank (PR).
Than I thought, I have to get Google Page Rank to earn more from Microworkers. I start working silently on my site and everyday I tried to publish at least one post on my site. I also tried to make all past unique as it is important to get page rank. Now my site got PR3 and I am working on Microworker par day at least of 2 dollar and easily now I can earn $50+ in a month from Microworkers. So, you may understand How to earn $50+ monthly from microworkers.
Now a days most high paid jobs on Microworkers are website based. If you like to submit high paid jobs, you need to have a website with PR. Your domain should be paid, do not work on free domain as all jobs are require paid domain.
Your site content should be unique, well decorated and not fake as these are the main key to get page rank. Of course visitor also a fact to make page rank. If you able to get page rank of your site more then 2, I hope you will earn $50+ per month form Microworkers.com