Tap nick in Address Book to open contact's page in the browser.
If you're using Mac OS X Leopard or Snow Leopard, download this tiny app, move to Applications folder and run once. Now you can click on those pushme://nick links in your Mac Address Book and have a browser web page opened.

It's no rocket science and not a separate application, the point is that since you can click those pushme://nick links on your iPhone, you can enter the information once and use it both on Mac and iPhone.
Download version 1.0 — PushmeToMac-1.0.dmg (245Kb)
Note: to enter a nick in the address book, choose "URL" type and enter pushme://nick.