I did a Master's degree in CS and have absolutely no regrets. It was, without a doubt, the most enjoyable, interesting, fun and educational period of my life.
In the 20 years since I have, at some point, found almost every subject that was covered useful. Most useful of all, though, was the education in critical thinking, critical systems thinking and soft systems. The lessons I learned there are ones I still use every day. Almost every job in technology involves, in some form, solving complex problems in complex, continually changing environments with many participants with differing interests, motivations and capabilities. This has stood me in good stead from my first job as a developer to my current role managing large programs of work.
My experience of StackOverflow users is that they are generally polite and very helpful although I've noticed a trend over recent month towards less tolerance towards people asking questions who obviously haven't even done a basic Google search first. I think StackOverflow users see it as a place to get answers to questions that aren't answered anywhere else on the internet rather than as a way of getting someone to do a Google search on your behalf. Not that I'm suggesting that this is your situation.
If you're looking for an alternative to StackOverflow where the quality of content and discourse is high then Forrst (www.forrst.com) is a great place. It's an invitation only community of web designers and developers which is in part, I think, what keeps the place friendly and helpful.
I think there's a business opportunity here. I too have been looking for a recurring billing service for a SAAS application I'm working on. As a small, Australian-based operation boot-strapping though, I'm really looking for a one-stop shop - something that offers the convenience of setup and payment of PayPal (no merchant account needed, reasonable rates, etc.) with the ease of integration and flexibility of Spreedly or Recurly and the ability to keep the customer on my site at all times.
In the 20 years since I have, at some point, found almost every subject that was covered useful. Most useful of all, though, was the education in critical thinking, critical systems thinking and soft systems. The lessons I learned there are ones I still use every day. Almost every job in technology involves, in some form, solving complex problems in complex, continually changing environments with many participants with differing interests, motivations and capabilities. This has stood me in good stead from my first job as a developer to my current role managing large programs of work.