I just noticed a subtle change in LinkedIn that is indicative of the importance of detail.  When a new contact accepted an invitation, LinkedIn used to send you a message with a subject line saying "John Smith has accepted your LinkedIn invitation".  The message was informational, and to be honest I never even looked inside the e-mail - I'd got the message from the subject line.

The new notification is subtly different: "Learn about John, your new connection".  There are four important differences in this:

• Firstly it only used the christian name in the subject.  If I want to know which "John" I am drawn into the e-mail
• Secondly, it is much more personal in tone, both because of the use of Christian name and also  "YOUR new connection" makes it about me and another person (not "your LinkedIn invitation" which is a bit abstract)
• Thirdly they removed "LinkedIn" from the subject - it's already there in the Sender field.
• Finally it is a call to action - it's no longer a passive notification but rather an invitation to learn more.

I suspect these changes will between the drive more people to read the e-mail content and click through to the site - which creates the possibility of advertising revenue and more interaction.

This is in stark contrast to an online retailer where the product page google had directed me too was only an information page.  To actually buy the product I had to go to the site homepage then click "shop" then search for the product again.  Why on earth did they make it so difficult, and how many sales have the lost because potential purchasers simply couldn't figure out how to buy?