ROI for Usability

[DrDoc]

I was just re-reading Jakob Nielsen's alertbox on ROI for Usability [useit.com] ... Has anyone else seen similar improvements on their sites?

annej's recent post [webmasterworld.com] inspired me to do some research to see how usability and accessibility has affected others.

[annej]

I find it's impossible to find a way to measure my ROI. Partly because I mostly use AdSense and it varies so much day to day anyway. Earnings have been improving but there are so many other things that could be affecting that like added pages, smart pricing, increase in unique visitors, and whether the ads served are appealing to my visitors or not.

Hopefully the improvements I've made in usability will help in the long run with increased returm visitors and more referrals to my site through incoming links, newsletters and word of mouth or mouse.