Great to see this news yesterday:
Starting today we’re rolling out the ability to export a copy of your Gmail and Google Calendar data, making it easy to back up your data or move to another service.
From Official Gmail Blog: Download a copy of your Gmail and Google Calendar data.
I’m not sure how well downloading 7GB of email is going to do in mbox format, exporting Gmail data hasn’t been enabled for my account yet. I like that Google is taking this step though, it is the right thing to do.