[akots]

- Development is being headed by creator Sid Meier himself.
This is very important and will probably ensure decent playability.

- Civ IV has been written entirely from scratch.
Apparently even more bugs and glitches can be anticipated.

- The 3D engine will allow you to zoom smoothly from a global view all the way down to a single city.
Usually these things cripple everything. Smooth zooming never works imo, there still will be levels and it will be glitchy. I'm thinking of camera view controls and RTW.

- Individual units will gain experience and acquire new upgrades such as bonuses against specific enemy types and the ability to use enemy roads.
Can make combat and movement too complicated. It is already rather complicated like it is, no need to add more features.

- No more spearmen defeating tanks.
Long overdue. Guess there will be free spearmen upgrades...

- Besides incorporating new technologies, the tech tree has been changed to allow radically different research paths to the same high-level technologies. ...
That is weird.

- Civilization IV has been designed to fully support the mod community. The game is written using flexible XML data files and the Python scripting language so that modders will have no trouble at all creating their own personalized worlds, units, technologies, and historical events. Advanced modders will even be able to control the AI.
Apparently this means modders will put more time to modding and less to playtesting their mods.

- Civ4 has been designed from the outset to include the multiplayer mode. You will be able to team up in co-op mode against the AI or other teams of players, and a random-map generator ensures an equal start.
This is not a great extra feature, this is essential must-be-there feature.

Sorry if it sounds sceptical.