While OCI can be an interesting factor to examine, the data was always somewhat inconsistent and is no longer easily available.

A more powerful insight into commercial intent can be obtained by examining something we at Noble Samurai call 'SEO Value'.

SEO Value (SEOV) is the total monetary value of traffic for a particular keyword based on the amount advertisers are willing to pay for Google Adwords and the volume of traffic that the #1 website in Google would receive for the keyword in question.

In other words:

SEOV = SEOT * AWCPC

Where SEOT = The maximum potential clicks the number 1 site in google would receive for a particular keyword
And AWCPC = Adwords Cost Per Click which is an indication of what advertisers are willing to pay for ads targeting that keyword

As this data is based on real advertising information, it is always current and provides a useful gauge to compare the commercial value of different keywords.