I'm curious, how do you handle this? Do you have multiple machines? Do you use something like rsync?
I don't keep 100% synchronisation between machines. I don't back everything up. I'm happy working at this level of granularity because it allows me to stay selective and not accumulate cruft due to relying on an automated backup of my entire drive. (In my case, backing everything up would result in a lot of useless noise.)
I'm not saying it's for everyone, but it works for me.
Version 2 is built in, but if you follow the directions at:
http://www.bombich.com/rsync.html
you can build a newer rsync that syncs all metadata.