Excuse the redundant post if backups are already in development.
Would it be possible to include the function in the client to create automatic (triggered on schedule or event such as receiving coin/generating id) and encrypted (eg. with AES) backup of wallet.dat?
The default settings, could be to keep 1 encrypted backup copy everytime something changes in wallet.dat.
The user could be asked for password and default save location on first run.
Even if users do not care about doing backups themselves, the software would at least protect them somewhat.
Also when I say encrypted, I mean encrypt the entire file, however if the private key encryption feature becomes standard then simply copying wallet.dat would suffice I guess.
The backup is essential imo, in order to protect oneself against catastrophic loss of all coins in the event of wallet.dat file being damaged due to the following:
a) sudden loss of power
b) hard drive failure in particular in the wallet.dat sectors
c) malicious software modifying/deleting wallet.dat
d) accidental/negligent erasure by user (ie. kids playing around with computer, reinstallation without backup etc)