Personally I quite like the style they've gone for. Can't say the actual graphics are as good as say AoC, but I like the actual style and realistic touch. You can have the best graphics in the world but implement them poorly by detracting from the realism with over the top bloom (Oblivion etc), or by going for a too cartoony a look. As long as they have nice details then Ill be as immersed as if they have the most realistic/top of the range engine possible. Thats just me though I guess..I could get immersed into the world of Ultima Online like 10 years ago

, mostly due to the details and feeling of realism from the game mechanics. This to me could be the most immersive experience even with graphics out of date by 5 years as long as it has the details right.
Think of AoC graphics in a 100vs100 siege on a city...it would just be wasted as you'd chug along at like 10FPS.
Anyway onto the actual game

. One of the other cool things about it is the real world tactics you can use. Theres going to be clans playing like its Total War

because you have body blocking and weapons have actual range etc. Theres a nice physics engine which will encourage this stuff. Imagine holding the high ground with 100 of your clan, some archers at the back maybe, polearms at the sides, dwarves at short range at the front (because of friendly fire from the arrows

) etc. Then you have a small cavalry unit hiding below you ready to hit the enemy at the right moment. Should be fun..but the smaller scale stuff is what i'll be involved in most of the time I think, especially 1v1. Weather also has an impact, so people might check the weather forecast and attack during rain or night time etc
This video should give you a few ideas of what you can do in DF, but it contains some things from the old engine (its on the second one now I think)
http://uk.youtube.com/watch?v=_bYYT6Wg3Gg
There was an official video released by them also in August in 6 parts..Worth watching em but I'll put part 6 which shows a city being attacked (check out the siege equipment

hover tanks/Warhalks lol)
http://uk.youtube.com/watch?v=NkXd9nzLnfw