Just a disclaimer here. This blog post comes from me as a DotNetNuke user, it doesn't necessarily represent the thoughts and opinions of the DotNetNuke Corporation, as I am not employed in anyway by the corp.
Well the time has come for the fear to strike the people. Today is the day that DotNetNuke Professional Edition is available, and to most of you that probably looks like a day to dread. The day the music died so to speak. But have no fear, just because there is a Professional Edition (read paid for) of DNN available doesn't mean that the project has lost sight of its open source underpinnings.
While true, there is a paid for version available and there hasn't been before, there is now a Community Edition of DNN available. What does that mean? You can get the EXACT same DNN that you've always had access to by downloading the Community Edition. The Community Edition will continue to grow, and will be the basis for everything that is DotNetNuke. The license for the Community Edition hasn't changed, it is still as open as ever. Infact, the license on DNN allows for ANYONE to take the software and repackage and sell it under a name other than DNN, I just had a blog comment the other day from a company doing just that.
So, you might ask, why would someone want a paid for version if you can get the Community Edition for free? The Professional Edition will offer you the following
Same day product support, performance guarantees, and copyright guarantees. (page with info about Pro). DotNetNuke Pro provides businesses with the assurance they need to run an open source application. While a lot of us (users) love open source, businesses tend to be a lot more hesitant to using an open source platform. DNN Pro is aimed at making inroads into those untapped markets, for the DNN Corporation and the rest of us. As the corporation gets strong, DotNetNuke Community Edition continues to get stronger providing a better experience and product for all of us.
So, when DotNetNuke 4.9.2 is released on Monday, you might be grabbing a new name, DotNetNuke Community Edition, but I assure you that you have nothing to fear, that product will be the very same DotNetNuke you have come to know and love (granted it will have some bug fixes in it 
)