The Macbook Pro 6,1 is highly compatible with Ubuntu 12.04 Oneiric.
Ubuntu 12.04 supports most all of the hardware on the MacbookPro-6,1 out of the box. There are a lot of different articles on this install which suggest different things of various complexity, but after reFit is installed, installation is standard.
install reFit http://refit.sourceforge.net/
- boot installation CD for 12.04 64bit version. (booting took LONG time)
- installed all updates
All hardware worked immediately.