How can you people NOT see the difference between the Xbox and the 360 versions of DOA...
Look at the skin in the Xbox version... it's flat in tone and color, it has shading but that's it... now look at the 360 version it has a realistic sheen on it reflectivity and radiosity....
Look at the clothing on the Xbox version the wrinkles, pocket, buckles etc. were all faked with textures... on the 360 they're all actually friggin rendered. Just look at the left player's pans in the 360 shot... You can tell the flames are embroidered on due to the higher poly model and normal mapping.
Look at the freaking environments. The Tree in DOA3 is a tube with a texture on it... the crap-tastic dock in the background that you can almost count the polygons from all the way in the foreground. Now look at DOA4... EVERYTHING in the background is unbelievable detailed not just high res textures but fully modeled and normal mapped, Heck look at the difference in the ground alone... every friggin bump on the bricks in DOA4 is normal mapped... DOA3 has a bland repetitive texture. In DOA4 EVERYTHING has appropriate reflectivity and radiosity... DOA3 has no reflectivity or radiosity in ANYTHING AT ALL.
Heck just look at the overall difference between the two... DOA4 is bright, vibrant, and crystal clear. DOA3 by comparison looks washed out and dull by comparison.
I think most of your complaints stem from "the people don't look real" well guess what, they're not supposed to. DOA is an anime style fighter... they're not supposed to look real they're supposed to look like vapid china dolls, that's the ART style, Ninja Gaiden is no different.
If you can't tell the difference between art direction and graphical enhancements then I don't think any of you will like anything that comes from Japan this next generation.