I have a bunch of tools that tell me what people have looked at on the net, including Google Analytics, Google Webmaster Tools, Clicky, and some Twitter tools. It's fascinating to see people's attention move around and occasionally reanimate something that I wrote months or years ago.
What these tools don't easily do is tell me what to write about next. Yes, sometimes they suggest missing things that should be expanded on, and looking at Twitter stats is endlessly fascinating. But that's a large part of the problem - the endless fascination gets in the way of applying fingers to the keyboard and creating something brand new.
It's easy to get distracted by the sorts of things that are meant to help you out. It's hard to be analytical and dispassionate about your past work while at the same time you're trying to create new work. Not everything worth writing has to rank highly on a search engine or get lots of referral traffic; sometimes, you just need to create something even if it's only for you to stretch your fingers.