How do I get Bridge and Lightroom to respect - read - metadata changes?

Question

I cull my wedding images in Bridge (CS 6) and then export them into LR 4.  I typically rate images as I'm culling, but when I import those images into LR, the ratings don't carry over.  Likewise, when I label images in LR and export them, Bridge shows all the color labels as white - regardless of which label was actually assigned. 

Answer 1

Lr saves all edits and any other metadata changes in its database (= the catalog).
Additionally to the catalog you can <save to file>,i.e. to a xmp-file (in case of a Raw photo), or in the header (but not in the image pixels!) of a JPG, TIFF, or PSD.
Saving to file is done by
_ either checking the box <Automatically save changes to xmp> in >Edit >Catalog Settings >metadata tab, or manually
_ by going >Metadata >Save metadata to file (in Lr Library Module), or
_ by going >Photo >Save metadata to file (in Develop Module.
When you save manually to file you can select multiple photos in the Grid Mode and do <Save metadata to file>.
This saving to file is necessary in order that Bridge can read and display the Lr edits because Bridge cannot read the Lr catalog.
Bridge saves to file automatically (there is no option of deselecting it) and Lr will read the metadata from Bridge when you import the image into Lr.
In case of an image that is already in Lr you have to select >Metadata >Read metadata from file (in Lr Library Module), or 
by going >Photo >Read metadata from file (in Develop Module). Without this <Read metadata from file>, Lr will not display any changes made in Bridge after the import  into Lr. Since this <read metadata from file> would overwrite any different edits you may have done in Lr, it is best to do this before you do further edits in Lr.
The rating stars should transfer from Bridge to Lr and vice versa without problems.
For the color labels to transfer correctly you have to make the textual descriptions for the individual colors identical in Lr and in Bridge - down to upper/lower case, commas, hyphens, underscores, etc.
Having said this:
I would recommend that you do not use Bridge for culling your images. You can do the culling just as easy in Lr. When you manage photos in Bridge and in Lr, you will always have the problem of synchronizing the metadata. This can be done but it needs a meticulous workflow that is adhered to strictly.
There is nothing in Bridge that Lr cannot do *). Make your life easier and choose Lr as your only image management and editing tool, except for CS6 itself (I mean Photoshop itself, not the ACR ).
*) Well there is one thing: Since Lr is not a browser-based program it does not automatically "see" what is on a hard drive. Photos need to be imported in order that Lr will "see" them.
Bridge is browser-based. Whatever photo is on a hard drive - irrespective of which program put it there - it will be "seen" by Bridge.
So Bridge is a valuable tool if a photo is not displayed in Lr and you want to check if it is in a particular folder.