This is frustrating as there was hope that things would change, but rather than bemoaning Outlook's lack of support for email marketing, let's take a look at what
will change with Outlook 2010.
Outlook will add a 'View in web browser' link to the message details if you have one of the lines of code below in your email. This in effect provides additional rendering support for your email via the recipient's browser.

Image courtesy of Litmus
CSS code to place inside <style> tags, in the <head> of your email
#ForceOutlook2010BrowserLink span { padding: 0px; }
Html code
<span style="padding: 0px;"></span>
We wouldn't ever recommend relying on this in place of testing for and ensuring renderability and you'll still need to add your own 'view in browser' link for recipients using other email clients. However it's a step forward by Microsoft to bolster their rendering issues.
From the looks of it, Outlook 2010 will not be having any great impact on the lives of email designers, so keep on doing what you're doing and remember to:
- use tables for layout
- keep the styling in-line
- avoid animated gifs for outlook users
- avoid background images and forms