Had the following issue:

I had Dead Money, Honest Hearts, and Old World Blues installed, way back when I had to re-install Fallout: New Vegas and never bothered to re-download the Classic Pack (Vault 13) I had gotten as a pre-order. As I was creating a new character I had remembered the pack, so I quit out of the game and downloaded/installed it. Upon going back into the game, I at least no longer had access to the Traits available for purchasing Old World Blues, and did not get any indication that any of the DLC had loaded through in-game pop-up windows while in the world.

I haven't looked further than that into it, as I am now re-downloading and installing all the DLCs just to err on the side of caution. I had also been updated to the latest patch.

Try this: http://www.mediafire.com/?2d08xkbs9uuny9j (will reset the injected preorder quests of any/all of the four preorder packs if loaded.

Edit: Sorry, I'd not noticed this was in the PS3 section. >_< Unfortunately, 'cause the forms from the preorder DLC packs are injected into FalloutNV.ESM, unchecking, saving, checking, then reloading won't reset the quests like it would with the other DLCs. The only way to wipe the slate clean on a PS3 would be to start a new character ={

Chalk this up as one more reason mods/developer console should, at least in some cases, be made available to console users.

No worries, appreciate the help none the less.

Follow-up: I Re-installed the game and all the DLCs (took a while, phew) and as would be expected, I now have access to my DLCs without having to delete my save files, thankfully.

Just as a side note, I had tried creating a new character while I was experiencing the issue and still could not access any DLC, most noticeably the Old World Blues traits.