Scott posts a few times each week about .NET and other web development topics. He’s a great writer, speaker and advocate for .NET developers inside Microsoft. His podcast is also excellent.
Joel Spolsky is the CEO of StackOverflow. Though he no longer blogs, his archives are full of detailed, well-written and well-argued analyses of programming culture, industry, and related business topics. The Reading List he calls out on his home page links to many of the best articles.
Chris Alcock posts a daily link round-up from around the .NET and web development communities.
Jeff Atwood ran one of the earliest programming blogs, though he no longer posts frequently, he is a welcome voice for .NET and other techy topics. He cofounded StackOverflow and more recently the Discourse project.
Eric Lippert was at microsoft for many years on the C# language team, working on the design of C#, and the Rosyln compiler suite. He has many excellent deep dives into aspects of the C# language and related framework topics. Required reading.
Phil Haack was once the PM for ASP.NET MVC and now works for GitHub on git tooling for Windows developers.
Few different authors post mostly about .NET, with a particular focus on performance and database technologies
Marc, a developer at StackOverflow, posts infrequently about .NET topics, particular Dapper, DNX and performance.
Another StackOverflow developer, Nick posts detailed expositions of the StackOVerflow system architecture and other .NET topics.
Mike Gunderloy posts a daily round up of about 3 links to items in the Ruby and Rails community with brief commentary.
Sam Saffron also works on Discourse, mostly on the Ruby side. He writes a lot about RoR performance.
Avdi Grimm runs a series of screencasts for Ruby developers and often posts helpful articles about Ruby, Rails, and web development.