I'm another programmer, I guess we all just like complicated things, or got here via stackoverflow.
Obligatory tedious but accurate point: Investing is not personal finance, in fact it's maybe one of the less important parts of it. See this answer: Where to start with personal finance?
Obligatory warning for software developer type minds: getting into investing because it's complicated and therefore fun is a really awful idea from a financial perspective.
Or see behavioral finance research on how analytical/professional/creative type people are often terrible at investing, while even-tempered practical people are better. The thing with investing is that inaction is better than action, tried and true is better than creative, and simple is better than complicated. So if you're like me and many programmers and like creative, complicated action - not good for the wallet. You've been warned.
That said. :-)
Stuff I read
In general I hate reading too much financial information because I think it makes me take ill-advised actions. The actions I most need to take have to do with my career and my spending patterns. So I try to focus on reading about software development, for example. Or I answer questions on this site, which at least might help someone out, and I enjoy writing.
For basic financial news and research, I prefer Morningstar.com, especially if you get the premium version. The writing has more depth, it's often from qualified financial analysts, and with the paid version you get data and analysis on thousands of funds and stocks, instead of a small number as with Motley Fool newsletters. I don't follow Morningstar regularly anymore, instead I use it for research when I need to pick funds in a 401k or whatever. Another caveat on Morningstar is that the "star ratings" on funds are dumb. Look at the Analyst Picks and the analyst writeups instead.
I just flipped through my RSS reader and I have 20-30 finance-related blogs in there collecting unread posts. It looks like the only one I regularly read is http://alephblog.com/ which is sort of random. But I find David Merkel very thoughtful and interesting. He's also a conservative without being a partisan hack, and posts frequently.
I read the weekly market comment at http://hussmanfunds.com/ as well. Most weeks it says the market is overvalued, so that's predictable, but the interesting part is the rationale and the other ideas he talks about.
I read a lot of software-related blogs and there's some bleed into finance, especially from the VC world; blogs like http://www.avc.com/ or http://bhorowitz.com/ or whatever. Anyway I spend most of my reading time on career-related stuff and I think this is also the correct decision from a financial perspective. If you were a doctor, you'd be better off reading about doctoring, too.
I read finance-related books fairly often, I guess there are other threads listing ideas on that front. I prefer books about principles rather than a barrage of daily financial news and questionable ideas.
Other than that, I keep up with headlines, just reading the paper every day including business-related topics is good enough. If there's some big event in the financial markets, it'll show up in the regular paper.
Take a class
I initially learned about finance by reading a pile of books and alongside that taking the CFP course and the first CFA course. Both are probably equivalent to about a college semester worth of work, but you can plow through them in a couple months each if you focus. You can just do the class (and take the exam if you like), without having to go on and actually get the work experience and the certifications. I didn't go on to do that.
This sounds like a crazy thing to do, and it kind of is, but I think it's also sort of crazy to expect to be competent on a topic without taking some courses or otherwise getting pretty deep into the material.
If you're a normal person and don't have time to take finance courses, you're likely better off either keeping it super-simple, or else outsourcing if you can find the right advisor: What exactly can a financial advisor do for me, and is it worth the money?
When it's inevitably complex (e.g. as you approach retirement) then an advisor is best. My mom is retiring soon and I found her a professional, for example.
I like having a lot of knowledge myself, because it's just the only way I could feel comfortable. So for sure I understand other people wanting to have it too.
But what I'd share from the other side is that once you have it, the conclusion is that you don't have enough knowledge (or time) to do anything fancy anyway, and that the simple answers are fine.
Check out http://www.amazon.com/Smart-Simple-Financial-Strategies-People/dp/0743269942
Investing for fun isn't investing for profit
Many people recommend Motley Fool (I see two on this question already!). The site isn't evil, but the problem (in my opinion) is that it promotes an attitude toward and a style of investing that isn't objectively justifiable for practical reasons. Essentially I don't think optimizing for making money and optimizing for having fun coexist very well.
If investing is your chosen hobby rather than fishing or knitting, then Motley Fool can be fun with their tone and discussion forums, but other people in forums are just going to make you go wrong money-wise; see behavioral finance research again. Talking to others isn't compatible with ice in your decision-making veins.
Also, Motley Fool tends to pervasively make it sound like active investing is easier than it is. There's a reason the Chartered Financial Analyst curriculum is a few reams of paper plus 4 years of work experience, rather than reading blogs. Practical investing ("just buy the target date fund") can be super easy, but once you go beyond that, it's not. I don't really agree with the "anyone can do it and it's not work!" premise, any more than I think that about lawyering or doctoring or computer programming. After 15 years I'm a programming expert; after some courses and a lot of reading, I'm not someone who could professionally run an actively-managed portfolio.
I think most of us need to have the fun part separate from the serious cash part. Maybe literally distinct accounts that you keep at separate brokerages. Or just do something else for fun, besides investing.
Morningstar has this problem too, and finance.yahoo.com, and Bloomberg, I mean, they are all interested in making you think about investing a lot more than you ought to. They all have an incentive to convince you that the latest headlines make a difference, when they don't.
Bottom line, I don't think personal finance changes very quickly; the details of specific mutual funds change, and there's always some new twist in the tax code, but the big picture is pretty stable. I think going in-depth (say, read the Chartered Financial Analyst curriculum materials) would teach you a lot more than reading blogs frequently.
The most important things to work on are income (career) and spending (to maximize income minus spending). That's where time investment will pay off.
I know it's annoying to argue the premise of the question rather than answering, but I did try to mention a couple things to read somewhere in there ;-)