I don't know, but I hope not; I've been doing rather a lot of it these past few years. Here's Yaacov's answer:
All of which is to say that I ought to blog less. Blogging is so intensely a matter of the moment, so irrelevant two days later, that it has to be a waste of time. I'm not saying I'll stop, but I ought to.
I'm struck by the 'all of which' that frames this, though. For it refers to... the histories of Venice, Florence and Jerusalem! Isn't that a bit of a tough benchmark? I mean, how would chatting to people fare when judged so? Or journalism? If we place blogging somewhere between these two poles - as a form of conversation shading into the articulation of argument and opinion - mightn't it fare better than when measured on the grand scale of historical achievement?