After reading the comments on Zeldman's thoughts on HTML email, I'm so glad I've never used it and still don't. So, for my Internet-enabled years I'm going on eight years of only reading and sending plain text emails. On the odd occasion that someone forces me into viewing an HTML email, I thank my dog that I don't have to look at that crap very often.
If I had a few more beers and some more motivation, I'd relate HTML email senders to the decline of modern civilization. You're smart so feel free to do this on your own 🙂