They sure do have scalability problems, in every sense of that word (both growth and viewport related) – thanks for pointing out Luke’s post. As to popularity, I’d agree with you. It’s quite handy when shopping, especially when you are exploring a category of product you’re interested in but don’t know much about. As I bet you are aware – and as Suroweicki and even the Pentagon have explored – “crowds” tend to know better than individuals. And although it sometimes seems questionable when applied to, e.g., a CD by Britney Spears, I do think that Amazon’s being open to popularity-influenced design therefore is not a bad thing. Another successful example of this – maybe without the scaling problems – is Apple.com’s iTunes. Much of the front page displays content or options that are crowd driven. And every search has an Amazon-like “people who bought this music also bought.” I’ve found it exceptionally useful for learning about, for instance, different covers of the same song.

And needless to say…the comment above is pretty much a lower-level encapsulation of your post on Zeldman’s article. There’s always going to be a tension between “high culture” taxonomy and tag clouds or folskonomies…I’d firmly agree that the place of the thinking man isn’t to resist the latter, necessarily, but to adjust and refine.

Does anyone know exactly when they rolled out this latest interface?