Selecting a Web Analytics tool is never an easy decision. There is no standard, scientific way to do so -- it's a bit of an art. The decision is full of compromises -- no one tool or fancy family of tools from one brand will be able to do everything you think or want them to be able to do. Nor will any one tool have all the bells and whistles you want.
Attribution has always been an issue for ROI-based Internet campaigns. Historically, ad servers have been programmed to credit attribution for a sale, download or other action to the last click from the IP address. But things are changing.
One of the most valuable lessons I have learnt from my previous career in database marketing is "never leave a marketing-related data decision in the hands of an IT person."
Advertising, it turns out, is a lot like physics; they're both all about time and space. Newspaper, magazine, billboard, and place-based advertisers buy space; TV and radio advertisers buy time. The online business originally aligned around a spatial construct (banner ads defined by area with two dimensions, and existing on a page); but increasingly, online advertisers are migrating toward a temporal construct, especially with the advent of online video.