Actually, thanks for this - it's the first time I've seen a good concise attempt at justifying the modern "minimalistic" UI approach.
Unfortunately, I hugely disagree with just about every point on the list.
colours should be limited and subdued for user interface elements so as to focus attention on content. Bright colours and animation are intended to call attention to important information.
Utter nonsense. I was never distracted by icons that had colour in them. I find it bizarre that anyone does get distracted by that. Perhaps they have ADHD. Whatsmore, UI elements are often important and get used a lot! Don't assume that just because it's not classed as "content", it's basically irrelevant. The removal of colour and complexity in icons has really pissed me off and made it a lot harder for my brain to discern what the heck an icon is supposed to mean. I am NOT distracted one iota by a colourful icon.
textures, gradients, transparency and drop shadow effects for the sake of visual flare cause visual confusion and eyestrain. Important elements get lost in the clutter otherwise
Only if you really overdo it. Some amount of this stuff is absolutely fine (see Windows 7).
ability to customize is often good but there can be too much of a good thing. If there are 100 "themes" or "skins"
So have a decent default skin, and let the people who want to apply another skin do so (see Winamp). There is no problem here.
Skeuomorphic Design has no business in UI Design
Yes, making knobs look like physical knobs looks dumb, so to some extent this is valid. But it doesn't extend to making every icon totally abstract. The brain has all sorts of images from the real world and it makes perfect sense to have icons and widgets often resemble stuff the brain is already familiar with. Any attempt to go against this for the sake of some holy design guideline is guaranteed to make the UI less user friendly.