At this time of this writing(Feb/15/2000), the games was announced only 2 hours ago. 
Basically, the only info is the press release, which however has some good information. The basic improvements over CTP I are:
- Game lasts from 4000BC to 2300AD (instead of 3000AD of CTP1)
- Improved diplomacy:
"A robust diplomacy interface will assist players in choosing their political stance, and allow counter proposals when dealing with other civilizations."
- "Ministers" and "advisors":
"Players who are inexperienced in managing an entire civilization may consult their ministers and advisors who will offer advice and make recommendations."
- Same graphics engine with improvements:
"Cities’ influence over the surrounding landscape increases as their populations grow."
- Borders:
"Borders between neighboring states are clearly defined to help prevent inadvertent skirmishes or international incidents"
- "Historical timeline" feature:
"A historical timeline gives players a holistic perspective on their civilization’s achievements over the centuries, and many units are presented with new graphics and animations"
- Improved(more realistic, historically accurate) combat:
"Combat in Call to Power II has been refined and rebalanced for more realistic outcomes"
- City "mayors" (ala civ2/smac advisors probably):
"The enhanced city management screen features automated mayors that help administrate the day-to-day operations of individual cities"
- Improved interface and menus:
"The interfaces and menus in Call to Power II have also been improved to simplify gameplay... improved build queue menus allow players to amass armies or build their cities’ infrastructure with ease"
- More ways to win:
"Players who choose to develop an aggressive civilization can achieve victory through military conquest. Conversely, gamers who prefer a more subtle approach can achieve dominance through scientific means."