The 'New Author Platform'

I'm currently attempting to get my head around the concept of author platform - what it means, how it has changed, and what a working 'platform' is actually comprised of.
I found this post helpful in clarifying all of the above - it doesn't seem quite so scary now (unless I think about it for too long...best just to get into it!).
http://www.alanrinzler.com/blog/2011/07/25/the-new-author-platform-what-you-need-to-know/?mid=56
Being a bit on the reclusive side, it's also enthusing me for 'the new' as opposed to the conventional expectations of traditional print publishing, as I'm grasping how much publicity and reader connection, even down to book signings, can now take place from the cosy on-the sofa seclusion of online presence and interaction.