Microsoft has confirmed they are no longer developing Outlook Express and have no plans to update the program in the future. You might remember not so long ago, we reported MS had said something similar regarding IE browser, the fact is, future releases will only be made available as part of the Windows platform & not as standalone releases.
"[Outlook Express] just sits where it is," said Dan Leach, lead product manager for Microsoft's information worker product management group. "The technology doesn't go away, but no new work is being done. It is consumer e-mail in an early iteration, and our investment in the consumer space is now focused around Hotmail and MSN. That's where we're putting the emphasis in terms of new investment and new development work."
Microsoft also intends people to upgrade to the full Outlook suite that comes with Office (especially when 2003 comes out). I'm not so sure how I feel about this announcement, although I have the complete Office suite, I'm more than comfortable with OE however I'm also in for any improvements (like in IE vs. Mozilla)... maybe it's a good time for start considering Thunderbird client.