No question that Com Org & US are in that order as far as overall current value, future potential, traffic and type-in possibilities go. They are clearly the top-3, with com and org in the top-tier, way out in front (all that TV advertising helps org greatly compete vs com), with US being a mid-tier extension.
All other extensions are lower-tier, with net info biz about equal but at the bottom and all about equally bad (sorry, I know many at the forums do not like to hear that). I never even look at sales threads anymore where I see the thread is mostly about net info and biz names.
Again, my analysis is based on overall current value, future potential and type-in's and traffic, and is not based on the resale market, which sometimes reflects other valuations. That includes a good degree of mass hysteria to get on the biz and info bandwagons, caused mostly by biz & info resellers and their strong market in Europe, Germany in particular, and the UK.