I often get asked which sites I like to use for research, so have broken my answer down into key categories, which should help. The blogsphere is constantly changing, so I’m afraid that a Google search tends to drill up numerous responses, which you’ll need to scan through to see whether any take your fancy. IMHO, blogs tend to be a matter of personal preference for writing style.

Some sites require registration or payment (e.g. Forrester) so if you’re looking for fresh thought you could try the big US universities like Wharton (http://knowledge.wharton.upenn.edu/)

Hope this helps

Good sites for research

• Interactive Advertising Bureau (http://www.iabuk.co.uk)
• European Interactive Advertising Association (http://www.eiaa.co.uk)
• Forrester Research (http://www.forrester.com)
• Brand Republic (http://www.brandrepublic.com)

Good for tracking the ‘buzz’ on viral campaigns and topics

• Google Trends (http://www.google.com/trends)
• Nielsen Blog Metrics (http://www.blogpulse.com/)

Good for viral

• ViralBank (http://www.viralbank.com)
• ViralMeister (http://www.viralmeister.com)
• You Tube (http://www.youtube.com)

Good for creative resources

• Moluv (http://www.moluv.com/)

Planners seem to like these sites

• Seth Godin (http://sethgodin.typepad.com)
• Russell Davies (http://russelldavies.typepad.com/planning//)

Good for understanding how far you can push the channel

• The Favourite Web Awards (http://www.thefwa.com/)
• Trend Watching (http://www.trendwatching.com/)