The new SPECIAL video for Luck came out today, and confirms that Luck now affects loot (beyond just perks that affect it). https://www.youtube.com/watch?v=Bke9wvob8Ls

The last time that Luck actually affected loot in a Bethesda game, was TES II: Daggerfall. If you had high Luck, you could encounter higher end armor/weapons much earlier than your Level would normally allow. Although, Luck did affect your chance of getting the Museum Oddities you could sell to the museum in Shivering Isles.

You must have missed the fact that there's a thread about the video, and we've already been discussing this there: http://www.gamesas.com/topic/1540192-luck-special-video

But while we're here, what led you to be so sure that luck definitely affects loot? In the video, the narrator says things like "scrounging" and "newfound fortune" - these refer to the first two luck perks, fortune finder and scrounger. Besides that, the video gives no hints that uck certainly affects loot on its own, it's up to the perks it seems.

Fortune Finder and Scrounger will affect loot, and they may have extra ranks for even more phat lute, but I don't think Luck itself will have a bearing on loot. The Luck description at E3 mentions loot, but the more recent video on the character system omits loot from the Luck description.

This was already know since the ingame footages...

http://orcz.com/images/thumb/6/64/Fallout4LuckStat.jpg/600px-Fallout4LuckStat.jpg

That's from the E3 video in June, the character system video that came out 3 months later in September no longer has the part mentioning finding better items, see the comparison in my post here: http://www.gamesas.com/topic/1540192-luck-special-video/page-3#entry24397502

Just like I said in that post, a guess is that the last sentence was referring to the luck perks fortune finder and scrounger.