i dont really think that 5000 wld replace 3800. it wld if not replace 602 then create a new segment above 3800 and smwt below 602 . if 5000 ends up creating a new segment then i guess 7000 is what all 602 upgraders should eye for . but then there would be a nice upgrade in price too for the those going for 7000 .
although the 3rd gen ccd sounds promising but i still cant reflect on its performance viz 2nd gen as i havnt been able to try my hands on it . but as i said earlier the artifacts should be minimized as the diagonal array of the ccd structure remains the same except for the little addition of smaller ccd cell on the diagonall opposite site.