Solid conversion
They have basically taken the pure essence of Civilization and crammed it into a DS. Some things are missing, like workers building roads or other enhancements. You can still build roads though, but they appear instantly in one round if you have enough gold to buy them. So, this part is different but it works just as well as before.
The only real complaint would be the somewhat crippled diplomacy. You can receive threats, but you can not issue threats to gain some favor from poor nations. This was one of the fun parts in the original Civilization though, so I missed it.
But, some nice additions have made it to the game as well. Like the cartoonish fighting sequences, which work much the same way as Advance Wars. This works well, and adds some excitement to the outcome of a battle.
I also enjoyed the rich amount of game modes that's featured. There's a long list of games you can start that has various twists to them, like unique goals or different starting points. For example you have a game starting off in another planet, where you have to fight for colonizing it. Others will set the world at constant war, or provide everyone with a lot of gold or other assets from the beginning.
I missed being able to customize each game a bit more though, by setting the world size, opponents and other factors.
I did not try out the wi-fi options, but I can imagine it's a bit slow to play a game like this with a friend. It literally takes hours to finish one game, and you most likely will want to use the save feature at one point in the middle. Finishing one game with a friend in one sitting may be possible, but probably not why you want to buy the game.
The game has many difficulty settings, so there should be something for everyone. Some things has been watered out, but I had to think carefully to remember what I should miss. The game works perfect for the format, and apart from some minor annoyances the user interface is painless to use and works very well.
Also new players can get into this easily, and helpful tutorials in the form of advisers will teach you every single thing about the game mechanics.
I only played the most basic difficulty level so far and found it too easy. Soon I had tanks butchering towns defended with archers. But, there's a range of difficulty settings so it should be easy to find the one that's right for you.
All in all an excellent strategy game, which will help you get through long, boring travels with its eventful long battles for bringing your civilization to victory.