It is amazing platform from one side but then I have been blocked as a "Robot" (I am not a robot and not using robots) after opening a community, so that's an issue that should be fixed...
Reddit is an excellent platform for discovering communities on nearly any topic. It's packed with engaging discussions, though the quality of content can be quite inconsistent.
I use Reddit in my professional activities. For me, it's an excellent tool for engaging with the gaming community and gathering feedback on game monetization. The subreddit structure makes audience targeting easy, while the voting and commenting mechanisms help quickly gather feedback from players.
Reddit is so big, it's difficult to make a general comment about it. There are so many strong communities on Reddit, and because it's a bit difficult to find your way at first, you definitely get a sense of belonging once you "get it".
When you're not searching for something, it's always a good place to stumble upon interesting content.
It's a great resource if you're looking for something specific, although the internal search isn't as good as using google and appending "reddit" to your query.