When hearing about the new features that Leopard OS X 10.5 were bringing, I was thrilled to see Apple Data Detectors on the list. Back in the OS 8.5 days, these were system-wide and you could customize your own data detection schemes. I wrote a set of ADD's that recognized scripture citations that would then look them up in Accordance. I can only hope that the possibility to add custom data detectors will be forthcoming. To date, you can only use Apple Data Detectors for calendar and contact information and they only work in Mail.app and iChat. Hopefully, that, too, will change soon.
Let me demonstrate to you how smart and how useful this technology is. I get lots of emails from my university and from church manifestations announcing info for meetings and events. Consider this email from my church regional office regarding a Men's retreat: If I hover of the date information with the pointer, it is highlighted with an outline to show that the technology is detecting an event description. If I click on the little drop down menu, I see an option for adding this event to iCal: After selecting it, the event is added to iCal, and look how smartly it deciphered the data. It even picked up on the fact that the following church name and address was the location for the event and added it as well: How quick was that? Notice the event event includes a link back to the original email for later reference. Wow. Thank you. Amen.
Update: If you won't ever be using ADD as they are and find the auto text highlighting annoying, you can disable the Data Detectors. In Terminal, us the command:
defaults write com.apple.mail DisableDataDetectors YES