The German site has an interview with Shafer and Newcomb, worth a read...
here I quote in Google translation:
about the "feared" diplomacy:
With regard to diplomacy reported some visitors to the fair Gamescom it, they would have had difficulty in establishing the diplomatic status of the world. So I said to Jon that, because especially for players who spend several days in long games, appropriate information needed as a reminder. Apparently Jon had also heard these complaints already, because he could already show a new screen for diplomatic information. Jon also pointed out that would continue working on Civ5 (also known Civ4 was further enhanced after the release of the patches with features). At this good tradition of the long-term support should therefore not change.
on Social Policies - do we get clear info about "switching", I wonder...?
The Social Policies / social policies should not be confused with the earlier forms of government even if they replace them. They are similar to my understanding more the specialization of role: as in a classical RPG available character points to certain classes and specializations will be distributed to form a character can, at Civ5 available culture points to specific social policies and specializations will be distributed to a civilization . form And how it would be interesting in a role-playing little, if characters could change their classes, specializations, and thus its identity ever free, it is likely to be less attractive if their specializations and civilizations ever to change their cultural identity could arbitrarily.
In Civ4 free choice of form of government is known to almost any time. For this reason, use later in the game as good as all the civilizations the same settings and are thus very similar - which the game is rather bland. On the other hand are likely to Civ5 on social policies, the differences between civilizations with a longer playing time increase ever - making the game more likely to be interesting. Perhaps this was the plaintive editor on the Gamescom still time not clear, because he could not play that long.
on modding:
In principle, at Civ5 similar range of options for modifications are available as in Civ4. Jon said specifically requests that, for example a Final Frontier as in Civ4: BtS could be realized without problems when Civ5. Instead of the scripting language Python is the scripting language LUA for Civ5 used, and in general should the requirements for technical modding skills are somewhat higher than in Civ4. There will also new modding tools, such as a game editor and a Modbuilder that creates a modification of an existing Modpaket. The interested parties can then select and install via the ingame Modbrowser. An installer you need as a modder so no longer develop, and for users to install mods is so comfortable and safer.
here I quote in Google translation:
about the "feared" diplomacy:
With regard to diplomacy reported some visitors to the fair Gamescom it, they would have had difficulty in establishing the diplomatic status of the world. So I said to Jon that, because especially for players who spend several days in long games, appropriate information needed as a reminder. Apparently Jon had also heard these complaints already, because he could already show a new screen for diplomatic information. Jon also pointed out that would continue working on Civ5 (also known Civ4 was further enhanced after the release of the patches with features). At this good tradition of the long-term support should therefore not change.
on Social Policies - do we get clear info about "switching", I wonder...?
The Social Policies / social policies should not be confused with the earlier forms of government even if they replace them. They are similar to my understanding more the specialization of role: as in a classical RPG available character points to certain classes and specializations will be distributed to form a character can, at Civ5 available culture points to specific social policies and specializations will be distributed to a civilization . form And how it would be interesting in a role-playing little, if characters could change their classes, specializations, and thus its identity ever free, it is likely to be less attractive if their specializations and civilizations ever to change their cultural identity could arbitrarily.
In Civ4 free choice of form of government is known to almost any time. For this reason, use later in the game as good as all the civilizations the same settings and are thus very similar - which the game is rather bland. On the other hand are likely to Civ5 on social policies, the differences between civilizations with a longer playing time increase ever - making the game more likely to be interesting. Perhaps this was the plaintive editor on the Gamescom still time not clear, because he could not play that long.
on modding:
In principle, at Civ5 similar range of options for modifications are available as in Civ4. Jon said specifically requests that, for example a Final Frontier as in Civ4: BtS could be realized without problems when Civ5. Instead of the scripting language Python is the scripting language LUA for Civ5 used, and in general should the requirements for technical modding skills are somewhat higher than in Civ4. There will also new modding tools, such as a game editor and a Modbuilder that creates a modification of an existing Modpaket. The interested parties can then select and install via the ingame Modbrowser. An installer you need as a modder so no longer develop, and for users to install mods is so comfortable and safer.
he asked the right question, but got the recycled answer from earlier interviews.. 
Your side actually made me join CFC-Forum because you link to it 
Thanks for posting the interview, Soma!
)