2 Spaces or 1 Tab, what's the standard for indentation in the Rails Community?

Question

I\'ve noticed that most of the HTML/XML/HAML that gets generated from plugins uses 2 spaces instead of 1 tab. I use textmate and have tabs set to 4 spaces for HAML/HTML/XML and

Answer 1

Two spaces are emerging as the standard because they are “just enough” indentation to make the HTML clearly indented to most people's eyes, but because HTML tends to nest very deeply — much more deeply than one would commonly nest when programming — and anything more than two spaces tends to start pushing HTML off the right edge of an 80-column screen pretty quickly.

Do not use tabs; use two spaces. Tabs are problematic because they can be a different width in different editors (and terminals, for that matter). Since whitespace is removed when you tidy your HTML before deployment, there is no ultimate bandwidth benefit to using tabs; they simply introduce a wildcard into your development experience.

I use Emacs, which auto-indents XML, HTML, and SGML with two spaces. I would be quite annoyed if I had to type indentation characters by myself; that's why I have an editor. :)