Lucas McDonnell lists 44 essential KM sites and blogs on his Uncommon Knowledge blog. I regularly visit abut half the sites he lists, so I need to go and check out the other half. I guess the term ‘essential’ is rather subjective, and what constitutes a good KM blog or site is very much a personal choice. My own list covers 20 or sources not mentioned by Lucas (listed on my blog sidebar). Discovering new and compelling web sites and blogs is all part of the self-learning element of KM.