Actually, I wouldn't be suprised if it happened in the next one. One of the complaints people have that I feel is actually valid, is that the dialog is kinda shallow. (your dialog, not NPC dialog). Less dialog choices = easier to record character dialog. Not saying it's a good or a bad thing, just that it's not unthinkable at this point.
Well, I think the reason it's like that is just because it's a skeleton-outline of your characters response.
When my guy says 'Sure, I'll do this for you.', I interpret more to his personality. For my Orc it'd be more like 'Can't handle your own problems? Alright, I'll do it.', while my Nord would respond more along the lines of 'I'll do it, if I get paid. Of course, I'll get your money whether you're willing or not.'
So, I tend to favor the more 'bare' approach to character dialogue in TES, because it allows for more branching to fit the character, as opposed to Fallout or Dragon Age.