Call me old-fashioned but I do prefer text-only email, and it should be viewed in a nice mono-space font like courier or monaco so indenting and formatting with spaces can be easily done. Here is a nice rant on HTML email from someone who has developed a web based email client.
I saw this recently and it made me smile:
() ASCII Ribbon Campaign /\ Against HTML Email
And look, there are several versions of the ribbon!
/"\ \ / ASCII Ribbon Campaign X against HTML email & vCards / \ _ ASCII ribbon campaign ( ) - against HTML email X & vCards / \
Hey don’t just take my word for it, ask Google.