they claim they improved the graphics, time will tell, but from what I see on the screenies, it's not much of an improvement, all in all, I love Disgaea for it's wickedness and dark humor, but in terms of visual entertainment it's really not that much to appeal, I was a little disappointed with D2, it was far too romantic for this kind of atmosphere, but the main guy wasn't really a demon so I dunno, i did like Rosa so I don't complain much on that, i liked D1 more since it was funny to see a priest with an Axe, or a brawler with a gun, and so on, making silly combos for weapons was really fun, and Disgaea 1 was much harder than others, I played the third game only by chance, but I didn't have much problems with damage control.
if D4 will have all that they claim to add, and updated graphics (I don't want the characters to be overly updated, the 2d characters in a complete 3d world were kinda fun to me, but the 3d effects could have been handled better if you ask me) then the game will sell fairly well, and not only to the male fan base.