HH - actually, you might be right. So far, it looks like nothing's changed since the previous update (or since the alpha, for that matter): all items within the player's sight range are highlighted with "ALT," with the exception of mostly junk (1-gold) items, specifically:

-bottles (not "empty bottles")
-broken bottles
-globes
-lab junk
-pillows
-plates
-potted flowers/plants
-tubes(?)
-vials

But I'm still testing as I play, so I'll post the final info in the UI Wishlist thread later.