It has been a long time coming, but it would appear that Valve is finally ready to make the move. Now that's not to say that what Greenlight is/was is completely going away, but the system is getting an overhaul. In Spring 2017 there will be a new service called Steam Direct.
Steam Direct will require new developers to complete a set of digital paperwork, personal or company verification, and tax documents similar to the process of applying for a bank account. Once set up, developers will pay a recoupable application fee for each new title they wish to distribute, which is intended to decrease the noise in the submission pipeline. They are still mulling around a publishing fee, but they indeed to do further research to make sure that they get it right.
The end goal is to hopefully allow the developers out there who might have the next million dollar hit to actually get the love and attention that it deserves, while decreasing the amount of shovelware that seems to always dominate in submission based marketplaces.