Being a more mature DS type, I see-sawed on this one for a while, and finally plunged in. I am old enough to remember the old Panzer General type games, and this is very much a chip off that block.
Historical details and facts are informative without being intrusive, and I found myself having "just one more turn" quite a lot! I was concerned that the "grand scale" may not have worked on the compact and bijou DS, but I found myself not noticing that after a couple of bashes. The zooming helps focus the wider picture, and the political and research elements add enough to make it a little more interesting.
The powers are nicely balanced - after smashing through the Low Countries, Denmark and France, I decided to quickly launch across the channel and snuff out those perfidious shopkeepers - to be thoroughly smashed by an all conquering Navy and RAF!
If you like your DS games a little slower paced and strategic, I would highly recommend this. Much more variation than End War, which is the closest equivalent I can think of.