MarketingProfs has pretty good articles.
Clickz Expert Column is pretty good read too, IMO - my fav section is ROI Marketing as that's most relevant to my profession...which leads me to my fav,
A long time reader/follower of grokdotcom - quality information.
A long time habit carried over from college years - I still read Harvard Business Review hahahaha.
Google Webmaster Central Blog is pretty good place for all levels of SEO IMO. Trollin' through Sphinn = ezmode access to good and bad articles hehehe. Despite what some people say about SEOMOZ, I think SEOMOZ offers good information. So yeah /shrug
Personally, I think Matt Cutts is pretty peppy and fun. Leaving the whole Google/SEO blog aside, rest of his blog is pretty fun IMO.
ComScore press release section has decent free statistics. C'mon...stats make you sound much smarter!!!!!
Too much good information - only 24hrs a day T_T