its not programming that is really different, yeah there is more, and you have a ton of pixel shaders to write (so your programming team will be a little large then a Wii production team because of that) but it doesn't equate to a massive difference in time... however..
...its the art work...
he amount of artwork required to produce art for the HD consoles is pretty insane. Building high detail models to build the base normal map off for skins and wall textures. build low detail models, build up a good specular map, diffuse map (base colors). all of that takes a-lot of time, in fact it takes over 3 times longer to build skins for a model today then say back in 2002, simply because of the extra steps one must take (esp in building a good normal map). Same largely applys with textures for map walls and terrain as well.
