The BIGGEST argument against HTML mail is that is seems to quadruple the
size of a message, and unlike here in the US, there are many countries
where the users have to pay not only per-minute phone charges, but per
minute Internet access charges.
i have subscribers to several of my mailing lists in parts of europe,
asia, africa and south america, and most of the out of country users I
have are paying by the minute charges. and for that reason, I do not
and will not allow HTML mail on my mailing lists.
Many mailing lists are out there to disseminate information, and I
don't know about the rest of the people out there but I pick up info
from messages faster if it is -all- in the same typestyle and color,
if someone has gone and colorized it or put weird fonts in so that it
looks 'cool' or emphasizes what -they- think is important, then that
is distracting from the message as a whole, as I may find some other
portion of their message important...