I've been using Linux Mint for almost two years now, love it.
Thought I'd mention an open source project I've just published called gAddressBookTool.
The package can be downloaded here: https://sourceforge.net/projects/gaddressbktool/files/
This software can manipulate VCard and CSV address books by merging records, distinguishing mobile numbers from landlines and reconfiguring their fields and text formatting of phone numbers, using a database of national dial plans.
I wrote it as I wanted to collect and merge all my address books - from Thunderbird and my old Nokia phone so that I could export it onto my android smartphone.
It is written in Python with GTK interface. I wrote it on a laptop with Linux Mint and using Geany IDE.