Need a post writing up some things users should know

I'm not sure what to call it, but we could use a post that lists these things users should know.  If someone has time to write it, here's the list:

- Make sure your clock is set correctly.

- Microsoft Security Essentials.  This never got written up proper.

- Warning not to mess around with your wallet.dat file.  It's a database file, it's not as simple as you think.  In this Beta version, we haven't had time to try and tinker-proof it yet.  It may not work as expected if you start swapping it around.