Gary Angel may yet be the most articulate writer on Web Analytics out there - he certainly gives us all a lot of information from which to evaluate a Web Analytic platform.  Unless your really using high end Analytics tools a lot of what Gary Angel says in his latest post might go over your head. I'll put it into my own words.

If you have a large site (I work on some large sites) you will need to categorize several pages by what they do or what business unit they belong to.  One way to represent a grouping is a "Directory" folder.  However you do it - you need to be able to say ….all press releases are in the press release grouping (folder); that way you can do an operation on a grouping (IE: how many uniques did I get to my Press room section of the site this week?); without categorization you'd have to go and select every bloody URL and do the operation individually then add them all up …a bloody mess and one big headache if you ask me!

But it gets more complicated as many URLs can not easily be put into a folder - be categorized by their URL structure - and that's what you need to look at when you select a package.

Besides, as Gary Angel points out ….. the newest innovations in Web Analytics tools tend to go to the subatomic level of the page (IE: the Web 2.0 part - trying to determine the performance of a part of a page) - that's certainly vital.  

" ….. For most web sites and web analysts, the basic unit of analysis has always been the page. And with the advent of widespread multivariate testing and Web 2.0, analysts are concerned about how to drive that level down a notch. There’s nothing wrong with that – both multivariate testing and Web 2.0 require that approach. But the simple truth is that lots of web site analysis and reporting is actually more interesting when you take the analysis UP one level – and look at behavior by groupings of content and not individual pages."

But what is also a problem - the ability to categorize large sites needs capacities in the other direction - in how you can manipulate several pages all at one time and de-duplicate visitors that are going to one part of the grouping so your not counting them multiple times.

After that - Gary's explanations go beyond my knowledge as I'm not a coder.

I'm finding Gary Angel's writings probably the smartest - clearest of anyone who writes about the practical problems of Web Analytics - you can take his writings engineer your decisions on them …. I am giving Gary a big compliment …. keep it up …I look forward to reading more of your writings on tool selection and other aspects of web analytics.