You're a smart guy and I'm a smart guy and we both agree on the mutability of the English language, but it's not always accurate or smart.
Irregardless.
Inflammable.
Point is, blog is perfectly accurate if we're talking about an online log (journal). It's not accurate if we're talking about a bulletin board, which isn't a log at all.
You're right, and I agree that it's happening. I can't help but resist it, however.
And here I thought perfection was not possible on this mortal plane! (joke) Obviously everyone has the right to determine for his self which definition he considers most accurate; however being understood by others is very different and requires a consensus. Most people consider "irregardless" as being nonstandard. OTOH, I react so badly when I hear people bash "inflammable" that my sinuses become inflamed.
The English language is like the American dollar. They're both mostly used by foreigners who need to deal with other foreigners and our sensibilities are not relevant. Since they're the majority we'll have to see where their censuses goes with "blog" if we want to be understood.