Thought I had lost my wallet forever, and then I realised Time Machine auto backups everything! So I got my wallet back and anyone with a mac could do the same if they lost their wallet 
Yes works well only had to use it once to get a file back it worked great then, one thing you may want to do though is go into time machines preferences navigate to your bitcoin directory and exclude everything but the wallet.dat from the backups. This will save you GBs of wasted space for backups for them always changing files that can be easily recreated anytime you run the bitcoin client.
