Having used them both a fair bit (though not to write novels, like some of the people on here): Markdown source is prettier to look at. This might seem minor, but it's the primary goal of Markdown. If I'm writing something highly technical, I prefer RST; if I'm writing something closer to plain English, I prefer Markdown.
I use Eclipse (now that I no longer have an IntelliJ license) for doing heavy-duty Java, but if I can get away with it, I prefer to do things in MacVim. Eclipse is just too clunky feeling when I want to do simple text editing tasks; it totally throws me out of my flow. That's why I'm on HN right now, as a matter of fact. So clearly, I am not an unbiased observer. That said: have you tried Pathogen/Vundle? Vim plugin management these days is light-years better than the equivalent Eclipse nightmare (I've given up on about half my Eclipse plugins as things constantly break).
For a lot of dynamic languages, at least, the templating engine is a surprisingly large portion of your page load times. I wish I could bring up the breakdown I saw a while back, but it's certainly non-trivial in many cases.
You won't see me saying that I think Groupon is a great value or anything, but I think that you have to acknowledge the difference between the people Groupon is reaching and the people FB or Google is reaching: Groupon's audience is people who are actively looking to spend money, whereas most of the people who see Google or FBs ads are doing something else entirely (and would probably not notice if they just went away).
These articles are cropping up because Google (quite cleverly) utilized the "We're Open" mantra to gain a lot of momentum very quickly. Since the evolution of Android shows more and more evidence of "We're Open When Convenient/Beneficial", a lot of their most ardent supporters now feel betrayed/played.
If Google had said "We're not as secretive as Apple", there would be less bitterness now, but there also never would have been the sort of momentum/buzz they built early on.