Nice article. I have a couple of notes though:

1) What you are describing is actually a simplified informal version of EBNF, not BNF (though the standards groups do use the formal versions). For instance it adds the ellipsis ("...") as a repetition operator as well as other common conventions. This is the language definition format used almost universally in Language Syntax Manuals since the 60's.

2) In English, these ("{ }") are called braces, not "brackets" or "curly brackets", or even "squiggly brackets". It seriously undermines the credibility of anyone talking about language definitions if they do not know the proper terms for the language that they themselves are using. (yes, it's a hot button of mine)

Still, very nice article.