Viral, inspirational, supportive or correctional, original, pithy, relevant, compelling, clear, solid, accurate, finite, and challenging... What a list! This gives us a lot to work on.
Thank you all for these insightful comments. I plan to personally apply your feedback in my own Blogs and I hope that visitors to this discussion find your comments as helpful as I do.
Joshua, you echo what several others have said and remind us that even if we hit all of the above, that the reader still holds at least half of the control. That's brilliant all by itself.