My votes goes to:
* Tom Warren
* Ian Griffiths
* Ars Technica (don't know who's best of them, but Ars Technica always write great, deep articles Smiley)
* Input from someone from the FreeBSD community would be nice: http://people.freebsd.org/~arved/bloglist.html
* Steve "Kernel Mustard" Dispensa (http://www.msmvps.com/kernelmustard/)