Google Contacts Merge

So I have been looking for the ultimate contacts management system for a while now.  Well the problem I always keep running into is being able to merge contacts.  Well friends, google has done it again.  You probably have all found this already but here it is.  Since I use google voice, this comes in real handy for being able to use one central place for all my contacts.  Google is it.  Exchange is great when you have access to it, but I wont be working for one company all my life, so I think google will be my life long repository for my contacts.  I think it would also be a little overkill to host my own exchange server.  Although, I would like the experience like these guys.