[mantlepro]

In addition to HTML, extra care should be taken for plain text rendering as well. Many users disable HTML and images to minimize tracking and malware. I'd definitely prefer a well formated plain text email with the option of viewing in the browser or email client if desired.

[i_am_nomad]

Or, a “degraded” HTML, basically an HTML to markdown converter, that keeps text-like formatting and drops things like images, scripts, and the like.

[erichurkman]

Most ESPs offer some kind of html -> text rendering. Most suck.

Mandrill's was OK, and so far, so has Postmark.

But nothing beats a hand crafted text template.

[inferiorhuman]

Or, a “degraded” HTML

No, plain text will do just fine.

[highesttide]

I absolutely agree that plaintext email should be kept alive, but is it really "many" for 99% of companies? I'd be shocked if anyone I know told me they disable html emails, even when I do it myself most of the time.