Thanks to a link from Robert Scoble (who is always looking out for his readers, bless him), my issue with Technorati not indexing my blog came to the notice of Technorati Chief Dave Sifry. To his credit, Dave immediately jumped onto the case and Kevin Marks solved it today. I noticed others have been having similar issues with Technorati, so I'll briefly summarise what the issue was and how it was fixed.
The problem was that outbound links from my blog were not being indexed by Technorati. Why was this an issue? Because Technorati tracks conversations and conversations are the lifeblood of blogs - e.g. I link to you, you notice my link via Technorati and respond on your blog, I notice your response via Technorati and respond in kind, ad infinitum (or is that ad nauseum!).
The Nub of the Problem
According to Kevin Marks, Technorati was indexing my weblog via my homepage and not through my RSS feed. But my homepage has excerpts and not full entries! So therefore Technorati was not picking up the outbound links in my entries. Kevin explained in an email that Technorati gave my homepage priority over my RSS feed "as usually the rss feed is an abbreviated form of the homepage."
Technorati now realise that they cannot assume a blog homepage will have the full text of a blog's entries, so they have corrected their parser. In fact, as I pointed out to them in a follow-up email, many of the Web Design blog community have only excerpts on their homepages (that's where I got the idea from). And a number of those folks also have excerpted RSS feeds, so Technorati may still need to adjust their code to account for people who have excerpted homepages and RSS feeds.
All's well that ends well
Anyway now I am happy, as my outbound links are back to being indexed by Technorati. My blog lives and breathes in the Sphere again! ;-)