Are you sarcastic? Is there some UN body or other collection of idiots that is actually going around using "Third World" to describe whatever countries are in need of it's poverty reduction mechanisms, or something like that? The term has always been understood to mean those countries that were neutral in the fight between the First and Second worlds during the Cold War, on account of their new independence. If what you meant was poverty in countries correlates well with cultural and institutional barriers to growth well, I have no quarrel with that, though that "in a sense" bit in your original post is doing a lot of work. But third world properly refers to a set of states which contain some of the most rational state-craft in the world, certainly better than some countries whose membership in the first world seems, at this point, to be mostly a matter of historical accident, though I'm aware that this is basically code for "set of circumstances I don't yet understand".
I genuinely didn't know that the third world meant "those countries that were neutral in the fight between the First and Second worlds during the Cold War,".
According to wikipedia, "The term continues to be used colloquially to describe the poorest countries in the world.", which was what I meant. The cold war is ancient history now, so I guess I'm just too young to have come across the former meaning.
Last Wednesday (2010 Dec 01), BBC Radio 4 broadcast a studio discussion on the question: "should we actively try to extend life itself?" The programme can be listened to from the BBC here for one week from broadcast, and is also being repeated tomorrow (Saturday Dec 04) at 22:15 BST. (ETA: not BST, GMT.)
All of the dreadful arguments for why death is good came out. For uninteresting reasons I missed a few minutes here and there, but in what I heard, not one of the speakers on any side of the question said anything like, "This is a no-brainer! Death is evil. Disease is evil. The less of both we have, the better. There is nothing good about death, at all, and all the arguments to the contrary are moral imbecility."
Instead, I heard people saying that work on life extension is disrespectful to the old, that to prolong life would be like prolonging an opera, which has a certain natural size and shape, that the old are wise, so if we make them physically young then old people won't be old, so they won't be wise. Whatever cockeyed argument you can construct by scattering into a Deeply Wise template the words "old", "young", "wise", "decrepit", "healthy", "natural", "unnatural", "boredom", "inevitable", "denial", I heard worse.
If I can bear to listen again to the whole thing just to check I didn't miss anything important, I may write something on their discussion board.