Alright already!!!

[I'm A Banana]

DnD4 is a 4th edition of DnD. Chances are that people interested in it are people interested in playing DnD and not Warhammer or Vampire or Burning Wheel or whatever. This is not to say that the comparison with those games is useless but I would argue that the most relevant comparison is with the previous incarnation of DnD.

Saying "3e's 'x' SUCKED! I had so many problems with it!" isn't a comparison. It doesn't have anything to do with 4e.

To go back to my car analogy, if I am wondering whether or not I should by a new sedan it is much more useful to me to hear how it compares with its closest competitor/previous model then how it compares with a pickup truck or a sports car.

But saying "The 10 year old model had horrible gas milage!" still doesn't say anything about the gas milage of the new sedan.

For me personally, DnD4 became interesting option when I realized that it addresses certain important issues I had with DnD3 - that information was easier to obtain given the discussion in terms of DnD3 then it would have been if we have been discussing DnD4 in vacuum.

It's useful to talk about what 4e does.

It's pretty useless to talk about what 3e does or doesn't do.

You can say "4e fighters have a lot of options! There might be a whole free-form stunt system!" without saying "3E FIGHTERS DID THE SAME THING EVERY ROUND! STOP SAYING 4E FIGHTERS WILL DO THE SAME THING EVERY ROUND!"

Criticism of 3e, by itself, isn't a comparison.

Saying something like "4e fighters will have more options," especially when it's disputed, will need something to back it up, rather than just "3e FIGHTERS DIDN'T HAVE ANY OPTIONS!" Even if it's true, it doesn't show us how 4e improves on anything.