> Hm. I just installed Windows XP out of the box, and Facebook works on IE6. That's as strict a test as need be applied.

I am laughing so hard. You need to put a little icon on the sites you develop saying "Best viewed in Internet Explorer 6," and be sure to post on the front page "Please set your monitor to 1600x1200" (or whatever your out-of-the-box resolution happens to be). Oh, that's right. We're several years past such practices by now. Darn. Yes, I know you work with a few browsers, maybe on some different boxen. But I hope you realize how silly you sound there. :-)

> Facebook has a fixed width. Is that anything new? Lots of site have fixed-width. Even if you're too narrow, can't you scroll normally?

Nope. Not in Firefox 2 on my OS X box. I can horizontal scroll abnormally, but not normally: I can easily scroll with the arrow keys, but scrolling with the mouse requires tremendous aim and coordination. Why? Because a toolbar element which sits perpetually at the bottom of the window partially covers my horizontal scroll bar. (Granted, I haven't glanced at Facebook in a couple weeks. I have no idea how it looks and behaves at this moment: http://news.ycombinator.com/item?id=515376)

If I were one of my non-tech-savvy friends, I would say, "I hate Facebook. Why does it do that at the bottom? I can't move it sideways! I need to get my friend to fix my internet for me. I hate computers." But instead I say, "I hate some aspects of CSS, and I'm starting to wish the DIV element had never been invented. DIVs are meaningless when they're put to so many arbitrary uses. Shameful."

I'm not keen on TDD, but a good takeaway from it is, "Only write testable code." When a page consists of a mass of nested DIVs and a tangled cascade of styles, when sizes and positions are controlled by a mishmash of width, height, top, right, bottom, left, border, padding, margin, float, clear, auto, px, pt, em, ex, %, you name it, the page is essentially untestable, undebuggable, and unmodifiable. Try to add an element whose position is fixed to the bottom of the viewport, and you're asking for even more trouble.

Facebook's horizontal scrollbar problem might be remedied merely by changing a margin spec somewhere to a padding, or vice versa, but I pity the poor developer who tries to figure this out. I'm assuming Facebook developers are not so idiotic as to not glance at their work in some different browsers with some different window sizes on some different platforms. But when a borked scrollbar shows up, it's a bad sign, for it means Facebook is creating something too hard to maintain. And ever more people will mutter, "Why does it do this? I hate computers."

When I say "maintain," I mean supporting a larger spectrum of users. A few weeks ago, I read that Facebook has 175M users, of which the fastest-growing segment is 55-year-old women. (Sorry I can't find a link now.) If a site reaches a point where it becomes "necessary" for functioning in civilization, it faces the nearly unimaginable task of supporting "everybody." For starts, try picturing people of assorted abilities on welfare using whatever systems happen to be available at a community center in a church basement. Good luck.

> Google sucks at design.

Today Facebook is hardly necessary to modern civilization, but Google's search might be. "Sucky" design means a web page can be used by a greater variety of people. And the daunting thought of becoming something like an infrastructure utility company probably has Google thinking long and hard about "everybody."

> There isn't going to be a "next" iPhone. There's the iPhone. The next big thing will not be compared to the iPhone at all.

Okay, whatever. I was just trying to dream up something that hasn't been seen yet. Maybe imagine a visual gizmo between a laptop and a handheld, something for which neither the @screen nor @handheld media type is quite suitable.