The site, from my  perspective, seems absolutely excellent. 

Easy to move around, and I love activity page and the latest activity on home page  for some reason.  I'm such a lazy git I like to be able to find what's happening as it happens.   Like idea of tag cloud (not seen that before).  Like Movers and Shakers (can find gurus (huh!) easily and their articles).  I noticed that on the articles page they are listed in most popular order.....took me a bit to find the "most recent" tab.....don't know why....needed to get my eye in?  I think I noticed someone commenting that they thought "most recent" articles should be more prominent rather than most popular.  For some reason, that idea appeals to me too.  But, as I think about it, as site receives more and more traffic, I guess I want to feel comfortable that the information in an article has credibility which the most popular lising gives you confidence of.   "Articles" are my nirvana in terms of building understanding in any particular area...I see Q&A, comments etc for the advanced user.

Looking forward to building my online marketing knowledge.