File sizes greyed out (strange extended attributes) in Finder on Lion?

I just got a new machine with Lion preinstalled. After transferring all my applications, I noticed that the file sizes (and only the sizes) of some applications and folders are greyed out:

Does anybody know what this means?

Update:

ls -la gives the following lines for DjView and Dropbox:

drwxr-xr-x   3 daniel  staff    102 31 Okt  2007 DjView.app
drwxr-xr-x@  3 daniel  staff    102  3 Mai 10:06 Dropbox.app

I.e. Dropbox.app has extended file attributes, namely

$ xattr -p com.apple.FinderInfo Dropbox.app/
00 00 00 00 00 00 00 00 00 00 FF FF FF FF 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Cheers

MrMage

I have only the craziest of guesses, but since we're all striking out so far, here goes.

Is there any chance you've turned on the Asepsis mode which installs a kernel extension? You may have not disabled that in your testing (a safe boot should confirm / rule this out as well). It seems possible that it's intentionally showing you which folders it has replaced the normal .DS_store file with entries in /usr/local/.dscache

I would also use mdls to inspect the metadata for these folders (since apps are really folders these days) in case some clue jumps out at you.

It seems that those Apps are only sym links. Maybe those apps are in your ~/Applications folder, and are linked to the /Applications one.

Could you check it.

Edited to reflect the edit of the author.