Dhruin
SasqWatch
Diablo III has been previewed in a meaty 6-page article at GameBanshee, complete with a gallery of over 100 screenshots:
More information.It really is a trade-off, with the new system encouraging smart selection of skills over simply min/maxing a key two or three, but it's also less involved, and once you find a few skills you like, chances are you won't feel the need to change them up, which potentially undermines the wide skill selection so emphasized by the "new skill every level" setup. Blizzard claim that Runestones will further enhance skills in different ways (turning a single strike into an area attack, or elemental damage bonuses), but they aren't included in the beta so it's impossible for me to draw conclusions as to whether it represents an improvement or not.
Attributes are still there, as well - Attack, Dexterity, Vitality and Defense - but they're all pretty static, even more so than skills, only changing based on bonuses given by items. Whereas attributes were deterministic in Diablo II, with multiple effects and influences per attribute (such as critical chance, blocking chance, etc.), now they're down to single effects mostly just influencing damage output. Once again, the loss to customization is substantial, and while it means that respecs aren't necessary if you make a mistake, it also cuts into the feeling of ownership of your character. Save for your items, nothing about your character build, if it can even be called that, feels very substantial or significant.
The net result of this is that Diablo III has a much more immediate feel than the prior games. Whereas much of Diablo II especially was about anticipating the next level-up, in Diablo III, those levels feel less like progress so much as they do expand your repertoire as the game's threats grow in number and complexity. I can't comment on the effects this might have on the game's longevity, but needless to say it can make Diablo III feel less like an RPG and more like a straight-up action game from time to time.