The publisher cites "technical reasons" for the delay. In the case of the RDR, the delay isn't actually such a big deal. The game's pre-order bonuses were pretty low key — adding in golden guns, additional costumes and a new horse. L.A. Noire's pre-order bonuses are a different matter entirely.
This is mainly because they come in the form of entirely new cases to solve. Given that L.A. Noire looks to be one of the promising releases of 2011, we're not too keen on missing out on any content. But we're also not pre-ordering the game from a trio of stores just to get everything.
Rockstar promises that the bonuses for L.A. Noire will be available from the PlayStation Store much more promptly. "For those of you inquiring about the expected availability of the L.A. Noire preorder bonuses as DLC after game release, those should become available as DLC much, much sooner."
Good, that's the way it should be. But it's still making good out of a bad situation. We're cool with peripheral things like costumes, themes and avatars being pre-order bonuses. Heck, even t-shirts and comic books are fine. But when you're only letting specific people access certain missions, that's where we've got a problem.