Did you ever have a really nice email newsletter designed for you and then get it sent to your inbox only to see it look different than you imagined it would. Typically that is because email applications both web-based (Gmail, Yahoo mail, Hotmail) and desktop (Outlook, Thunderbird, Apple Mail) are all very different.
That’s not good at all for those of us who build email campaigns for our clients. There is this great group called the Email Standards Group, that was just formed about a year ago, that champions the cause for standards in email programs displaying HTML. They recently released an ‘acid test‘ so that you can send a standards based email test message to your personal email application and see for yourself how tough this stuff is.