We all want to measure the progress of our site(s) in as many ways as we can. This is why people obsess about things like Google Page Rank, Alexa rankings, and other things that really don't matter very much. And who can blame us? While these measurements are highly flawed, they are among the only external methods of measurement that we have available.
We have more extremist people who carefully watch the behavior of different data centers. This is a prevalent enough activity that Matt Cutts did a video about it. This particular practice does not seem to add any value at all from my perspective.
In addition, as we head into the future of personalized search, what people obsess about is going to need to change. The focus will shift to looking closely at stats that measure user interaction with their sites. Things like "bounce rate" and "page views per visit" will become increasingly important.
Frankly, these things are critical already (because they speak to conversion rates), but now they are likely to become a factor in your search engine rankings. It will be our new obsession as we enter into 2008. Of course, if you want to position for yourself for success now, start thinking about your users first, before worrying about the search engine. It just might get you a leg up on your competition.