Various methods for switching to Gmail and bringing along your old mail have been discussed to death in the blogosphere, I know. Gmail does turn four next week, after all (it was released to the public on April 1, 2004; April 1, 2008, is next week). Since its release, Gmail has added lots of features, including IMAP support.
Ordinarily I wouldn't bring up something that's already been done before (well, anything that was last posted about more than a week ago). However, the Official Gmail Blog posted a short set of tips for moving to Gmail, and I thought I'd sound off on the list. (Comments are turned off on that blog, and I need a post anyway.
So, despite the title ("Tips for importing old email to Gmail"), the only things we find out are that we should set up POP retrieval on all our old accounts and enable sending messages as those old addresses just in case. Nothing is mentioned about getting mail from email clients, which has been deleted from the POP server, into Gmail. And nothing is mentioned about getting mail out of e.g. Hotmail or Yahoo! Mail (which are, admittedly, pretty difficult as they don't support POP access anyway).
Various solutions for the desktop-client problem have been posted in the years since Gmail's launch, as I hinted earlier in this post. (I haven't seen any good solutions for Hotmail/Yahoo! Mail yet.) Some rely on automatic forwarding scripts, others on the new IMAP support (Zoli Erdos has a good write-up of the IMAP method, which I would like to try when I get the chance).
What irks me is the fact that none of these ingenious solutions for getting already downloaded mail into Gmail. If you use a client like Outlook Express or Thunderbird (Mail.app, Outlook, Eudora… the list goes on), Google can import your stuff if you get a business-class Google Apps account, which supports email migration. But that would be $50 a year. (The migration API on which the migration tools are based is only available on Google Apps-based Gmail accounts, unfortunately.) Granted, the solutions that simply forward everything to your account and ruin all the headers probably aren't all that useful; but the IMAP–based methods would probably be quite useful. It's just a drag-and-drop from local mailbox to Gmail.
I hope that tips for uploading email from offline clients get posted to the Gmail blog sometime in the future. Preferably in the next few months, but anytime in the next up to two years would be fine by me. It had better be before Gmail's tenth birthday, though.
Oh, and rest assured, I will try the IMAP import method as soon as I have the time. That will probably be around June, after school's done for the year. Cross your fingers for me in advance? (Thanks if you did!
Update (04/01): Just got a comment from Zoli Erdos, who brought my attention to the text surrounding the link to his site. I cleaned that up; it didn't make much sense before. So this update is really just a short series of edits. I've marked my inline insertions up with <ins> tags for visibility. Thanks for bringing me back here, Zoli!