raw, xml, jpg.... help with files and bridge

so recently i went from cs2 and lightroom 2 to cs4 and lightroom3 and started using adobe bridge and now i've got all these .xml files i never had before. do i need to keep those?

how do you all organize your photos? do you just leave all photos in one folder and use bridge search with keywords to find what you want? i usually used a folder titled photos that had subfolders titled, photo sorting, raw files, animals, people, landscapes ETC. this is starting to be alot to keep up with when it comes to manually backing up each folder from local disk c, to local disk d and external disk j. theres got to be a better way?

.xml or .xmp?

If the latter: The file is created if you edit a CR2 file in ACR or (depeninding on prefs) LR.

I'd use LR for cataloging and finding images.

You either want to work through Photoshop/Bridge as your "main" workflow app or move to Lightroom. Have you done any reading up on the two apps?

i've used lightroom but just started using bridge because of how great scott kelby made it sound in his cs4 for digital photographers book. yes its xmp. i usually upload all photos from camera to a folder called photo sorting then manually move each file to another folder that describes what it is. i've never renamed or keyworded untill now trying to make things easier.