Although it's probably futile, I'll still give it a try.

I can see in your tutorial that you desire 4 spaces over tabs. I have 
never seen a good argument for spaces (and I've seen a lot), so I'll 
try to convince that tabs is the way (god damn it we don't live in 1980 
any more).

From the tutorial: "Tabs introduce confusion, and are best left out." - 
only if you're switching in the middle of a document, tabs and spaces 
are equally confusing (I would say they're the opposite, but ok). 
There's no difference on that part.

Then some of the arguments I've heard is that some editors shows tabs 
badly, although true, then most proper editors it's possible to adjust 
that to your personal preference, removing that possibility you are 
removing a nice (although not entirely needed) flexibility.

In a program with 200 lines of code we have roughly 600 extra 
keystrokes with spaces, unless using a proper editor which shows tabs 
nicely.

Tabs use less space, which is usable when uploading and downloading 
code a lot (which you do when using version control).

Posting on forums is a problem with tabs. True, but then you can use 
proper utilities for that, and although I don't use forums for code 
issues I would seriously question the forum if a code-related forum 
didn't convert tabs, and even if it doesn't then I would still use a 
pastebin utility, since it offers all those nice features like syntax 
highlighting and auto conversion of tabs.

4 spaces is prettier than tabs converted to 8 spaces. True but yet 
again most editors can adjust that or actually use 4 spaces per 
default, but if I like 2 spaces I can't do that without introducing 
confusion, so spaces actually introduces more confusion than tabs.

Good editors makes spaces transparent and behave like tabs, true but 
good editors also makes tabs look pretty. But editing manual spaces is 
hell compared to the ugliness of a bad editor, and I prefer usability 
over pretty.

This don't look good with tabs
string = "some multiline whatever string"+
         " and continued"
string = "some multiline whatever string"+
            " and continued"
True, but not unreadable, and if insisting on pretty you can switch to 
tabs for identation spaces for multiline prettyness.

So until I see good arguments for spaces I would really like to see the 
standard switched to tabs, since I see no good reason for claiming 
spaces is better ... actually so see reason to claim otherwise.