Most of you are comparing my 'broken lore' examples with real-world lore.... Hairless molerats break lore/canon because they are hairy in the previous games.... The fact that there are real-world hairless mole-rats is irrelevant....
Bottlecaps are anti-canon since the concept has been advanced in previous games, and because (while this opens a whole other debate) it's unreasonable to expect coasts- disconnected from each other, to both pick the same random item as currency... Bottle caps don't make a ton of sense already when mankind has been using metal coins for thousands of years....
Things like game-balancing allowing for fast ghouls or different centaurs are also not good reasons for lore breaking.... The debate shouldn't be whether they COULD have done it otherwise... The fact is: They changed it without valid game-world reasons....
This stands for exploding cars, Harold, etc...
While the dumb supermutants might not fit my rules, I stand by the rest of my examples as breaking the existing lore established prior to Bethesda taking over...
Really, I think it's just a matter of how attached you want to be to every little detail. Maybe it sounds like I'm saying "don't sweat the small stuff," but really - in the grand scheme of things, all this so far is - even if I were to concede your point - pretty minor stuff.
And some of those actually aren't "breaking" any canon:
There was nothing in existing lore previous to Fallout 3 that said Harold couldn't have (don't want to have to resort to spoiler tags) ended up how he did. You might find it odd, you might not like it. But that doesn't mean there's a contradiction, there. That's adding onto existing lore, sure. But... that's kind of going to happen. If back in Fallout 2 Harold had said "yep, good thing this tree growing out of my head isn't going to get any bigger, absolutely no chance of growing any more than this," then yeah, that might be breaking something. But he didn't. So it doesn't.
Exploding cars kind of fall into that same category, as well. There's nothing to contradict. There were no exploding cars in Fallout 1 or 2, given. But no one ever said "gee, sure am glad none of these cars can ever blow up..." So that's another addition, but there's nothing previous for it to break.
And anyway, the rest of this so far? That they actually kept an iconic currency from the original game instead of just calling it "money?" That centaurs - failed genetic aberrations - look different? You have to admit that's pretty small stuff in the grand scheme of things. I know you're not losing sleep over any of this stuff. I don't think even the guy who originally modeled the centaur for Fallout 1 exactly shed a tear when he saw what the new ones looked like. Sure, those are two things that are objectively different, without an in-game explanation, even if it's pretty easy to rationalize. By that definition, they qualify as "lore-breaking." But I don't think we're actually going to argue that it's really all that big of a deal, either.
As far as Ghouls go, however, I'm standing my ground on this one. Sure, they did a lot of shuffling around. But I'm going to remain adamant that they got some extra movement allowance during combat - because the only enemy that could close the distance more efficiently than them seemed to be the wild dogs. It took a long time for their animations to get them there in one turn, but the fact was that they could run up a good number of hexes and still have AP left over for a melee attack. I'm saying maybe the animations for Ghouls in Fallout 1 and 2 didn't exactly match what was happening in-game, but that game-wise what you see in Fallout 3 is basically what was being represented in the previous games, as well. It would have actually gone against canon, I would say, if in Fallout 3 they were stuck shuffling towards you like zombies.