I've noticed recently items and npc's sinking into the landscape. I put some dragon scales on the table in the Shroud Hearth Barrow area and they just dissapeared. I don't remember this being a problem before. Was this always a problem in Skyrim? I am experiencing this after the newest patch, I think.

Never heard of that. I occasionally get dead bodies turning invisible after killing them though. Bit annoying.

http://i1157.photobucket.com/albums/p586/Jopdepic/ScreenShot24_zpsc1ac626c.png

I've had this happen a few times (on Xbox) usually with really small objects.

And not just in Skyrim. It happens in other games too.

I have noticed this also, though I think the first time was before the latest patch. I have pounded mudcrabs literally into the ground and cannot loot their nice chitins. If I am lucky, their claws stay above ground so I can target them. I have also had this happen once or twice to bandits out in the world. I kill them and they fall into the ground so I cannot loot them.

[EDIT]
I play on PC. I have all 3 DLCs and the two mods for craftable Thieves Armor and unenchanted Nightingale Armor. I also use the Unofficial Patches and high res packs.

I'm playing vanilla Skyrim without any DLC or expansions. I don't remember having this problem before this years patches.

Getting this as of yesterday.

I had Serana following me, then she just disappeared, and I didn't think anything of it. Later, I walked into my Lakeview Manor, and I could just see the top of her head in the floor.

Not sure what it is or why it is.