Google has released a Mac version of their Email Uploader which enables transition to Google Apps even easier. If you’re a Windows user you’ve had this capability for a while already.
Essentially this uploader helps you migrate your email messages from Apple Mail, Eudora and/or Thunderbird. You will need a Google Apps for business as this doesn’t work for a regular Gmail account.
And, we use it at my full time job at North Point Ministries. I mean, it’s just the bomb.
Are you using Google Apps? Are you considering the migration?