I have all my favorites on feeds, but I normally land on Darren Rowes Problogger blog or performancing.com
Problogger is my fav too. I have a folder in my bookmarks called 'sites to visit at least once a day' and his blog is in there. I've learned tons from reading his posts.
Visiting most often: MattCutts' blog. Also: Summer's blog and there are others that I come across again and again. lately blogging has been pretty slow. I have to and will start making a list of the good ones as I come across them from now on Added Roman 1 has a cool blog and many others here do as well