I see a lot of presentations hit Hacker News that aren't very useful on their own because they were meant to accompany a talk -- and a good talk usually omits the best material (or a at a minimum, important context) from the slides.
This is probably one of the best presentation about the basics of web design that I know. He also mentions the book, Designing for the web, in the presentation which is a good entry for typography, colours etc http://designingfortheweb.co.uk/book/index.php
I've looked at lots of design for developers presentations, the topic must be guaranteed link bait. None of them really were all that helpful to me until this one.
I've only met two developers in my career that were were world class at both programming and design. People are looking for a magic shortcut to grokking design that just isn't there. The best solution for me right now is to use Bootstrap but there really isn't a great alternative to hiring the best designer that you can find.
The one I know through a friend of a friend has had multiple apps in the top 100 overall, App Store. And he is a better designer! And so hard on himself (e.g. you see his design and you think it is done and he keeps on going...)
"Just ﬂipping the gradient direction is the equivalent of the environment light changing direction when you hover over/click a button, this makes zero sense."
Inverting the gradient for pressed down button can also be seen as a convex surface becoming concave; think a membrane button. (A flat button wouldn't have such a gradient.)
While that kind of "faux membrane" buttons are not very common in real world, the inverted gradient effect immediately gives me feeling of "popped in" button. Am I alone here?
A radial gradient, on the other hand, might more typically assume an 'oveerhead' light, which is why inversion makes sense.
Of course the context plays a role too on the perceived illusion; the appearance of changing light source may be stronger for lonely button (vs. group of elements sharing the same light source).
One thing I don't get is the font sizes. At one point, it says something like "notice we're using 24px to tie into the multiples-of-6 rule", but elsewhere recommends 16px as the main base size.
I like this multiples of 6 thing, too. Most attempts to get a baseline grid going (like on Blueprint, for example) just look wrong.
People who are recommending to hire a designer, I would add that its quite a cultural thing. Not every designer is good at UX. Most of the designers in my country are more into graphics rather than thinking of how to use good color combination and typography.
Sufficient contrast is important. Worse still I have color blindness so for me contrast is critical sometimes.
These effects need to have quite a gentle contrast between the darker and the lighter colours, and if you start throwing around 25%+ differences in grey level your results could become overpowering for viewers with decent screens.
Of course, in such cases, you also won't completely break your design for viewers with poorly configured screens or imperfect vision if the contrast isn't as strong to them, so you can afford to be more subtle than when choosing, say, foreground/background colours for body text.
I tend to get instinctively defensive when people from other professions make assumptions about mine based on a limited understanding.
I didn't bother to cite it before, but there's a pretty well known study in this area: http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
Surely you don't mean that web apps that look like 1999 desktop apps are not good design?