As the Helium summer reward-a-thon ended September 22nd and the payments got issued on October 3rd. It took around 9 days to get the payments in my bank account, but they did arrive and so far this is my third payment and no mistakes have been made so far.
This payment was around $170 for writing one article every 3-5 days, that is a credible amount. The articles are also earning me $5-8 on monthly basis because most of them are ranked in the top quarter, giving me more search engine hits.
But as the reward-a-thon ends, so does my writing for Helium. If a new Reward-a-thon is introduced, then I will start writing again. So far I have earned over $300 and I am not really a good writer; just have a lot of general knowledge.
If you are a serious writer, then you can make money from the Helium Marketplace, where you can sell articles for $16-$300 per piece.
I have more writing stars, making me eligible for a higher payment for reward-a-thons, so I will definitely be writing more if more competitions are introduced and my next payment will be huge; predicting around $700.