Hotmail users of the world, revolt!
As many of you already know from this PLUG thread, the mail servers for MSN and Hotmail have been doing something despicable, for quite some time now. They quietly delete email that they think is spam, after accepting it for delivery.
Now, depending on your experience that may sound like no big deal, or it may rival the best plot ever for a horror movie. Let me explain why this is worse than zombies.
First, an analogy. If you put a stamp on an envelope and send a letter to your friend or business associate via the postal service, you expect it to get there. If you send a package via UPS you expect it to get there. You don't expect the recipient to show up at the post office to find the postal worker wearing the sweater you sent him. The mail may have been delayed, but it will get there. "Neither rain nor hail nor sleet nor snow nor heat of day nor dark of night shall keep this carrier from the swift completion of his appointed rounds."
If you show up to the post office with illegal mail—something that is outside the allowed dimensions or too heavy or has explosives in it—you will be told that you can't send it. You'll know you need to get a different envelope, pay more postage, etc. You have feedback. If you send mail to a bad address, or someone who hates your guts, you will get your mail back marked "Return to Sender" (assuming you provided a return address). Feedback. In neither case would you be satisfied if the post office just threw your important correspondence in the trash.
So, why would you accept this behavior from your email provider? When I send an email to fred@hotmail.com (whoever he is), and hotmail's mail server says 250 Queued mail for delivery, I expect fred will get my email. Maybe it's in his junk mailbox. Maybe fred is away on vacation and won't see it for a few months. Maybe it takes more than 5 minutes to traverse the internet. But I expect it will get there, or that I will get a bounce message if it doesn't. The reliability of email depends on it. The rules demand it.
If you use Hotmail or MSN, you have been losing email. I dare you to prove otherwise. You owe it to yourself and to the people with whom you correspond to switch right now. GMail is an excellent alternative. It has more features, better spam detection that doesn't delete mail without asking, a nicer user interface, more storage space than even you will use, and POP3 and IMAP support. While you're at it, if you use MSN for instant messaging switch over to Google Talk or, even better, Jabber.
If you have been corresponding with MSN or Hotmail users, your emails may have been trashed before the recipient ever saw them. They may not even realize this. Do your part and inform them. If they don't want to switch to a sane email service, then insist on communicating in a different manner.
And let this be a lesson to you: don't let the quest against spam (or anything else) turn into tilting at windmills. Keep your wits about you and consider the consequences of your actions. Especially if you're a system administrator. Really especially if you're a system administrator at a big email service like Hotmail. And that goes for SPF, too.